Make most of functions const correct (#714)

* Make most of the functions const correct

Used clang-tidy and sonarlint to help find places where const could
pretty easily applied. Also lot of hand work.

This commit does not yet touch handlers and typedefs of those.

* Fix Arduino uno handler_who_is() has extra parenthesis

For some reason there is extra parenthesis. Remove it this is more
likely buildable.

* Bugfix/bacapp: Fix uninitilized array_index

We have changed bacapp_snprintf_value() to be const correct. After that
we got

```
/home/runner/work/bacnet-stack/bacnet-stack/src/bacnet/bacapp.c:3183:27: warning: 4th function call argument is an uninitialized value [core.CallAndMessage]
                ret_val = bacapp_snprintf_weeklyschedule(
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.
```

So analyzer could now spot that we do not actually initilize array_index
at all. Fix this by setting array_index to zero. Note that I actually do
not know if zeroing is right thing to do here. I choose zero as if this
has worked before it is most likely that it will work with zero value.

* cmake: Add and ignore Wwrite-strings compiler option

Wwrite-strings helps find places where const correctness is broken.

Example it will warn about these

```C

void func1(char* str);

func("test") /* "test" is const so we should not pass it to func1().

char* func2()
{
  return "test"; /* func2() should return const char*.
}
```

We still need to ignore it as not all are fixed but let's add it already
so we remember that it should be opened at some point.

---------

Co-authored-by: Kari Argillander <kari.argillander@fidelix.com>

src/bacnet/basic/object/netport.c

@@ -92,7 +92,7 @@ struct mstp_port {
 
 struct object_data {
     uint32_t Instance_Number;
-    char *Object_Name;
+    const char *Object_Name;
     BACNET_RELIABILITY Reliability;
     bool Out_Of_Service : 1;
     bool Changes_Pending : 1;
@@ -314,7 +314,7 @@ bool Network_Port_Object_Name(
  *
  * @return  true if object-name was set
  */
-bool Network_Port_Name_Set(uint32_t object_instance, char *new_name)
+bool Network_Port_Name_Set(uint32_t object_instance, const char *new_name)
 {
     unsigned index = 0; /* offset from instance lookup */
     bool status = false;
@@ -746,7 +746,7 @@ bool Network_Port_MAC_Address(
  * @return  true if object-name was set
  */
 bool Network_Port_MAC_Address_Set(
-    uint32_t object_instance, uint8_t *mac_src, uint8_t mac_len)
+    uint32_t object_instance, const uint8_t *mac_src, uint8_t mac_len)
 {
     unsigned index = 0; /* offset from instance lookup */
     bool status = false;
@@ -2109,7 +2109,7 @@ bool Network_Port_Remote_BBMD_IP6_Address(
  * @return  true if ip-address was set
  */
 bool Network_Port_Remote_BBMD_IP6_Address_Set(
-    uint32_t object_instance, uint8_t *addr)
+    uint32_t object_instance, const uint8_t *addr)
 {
     unsigned index = 0; /* offset from instance lookup */
     bool status = false;
@@ -2326,7 +2326,7 @@ bool Network_Port_IPv6_Address(
  * @return  true if ip-address was set
  */
 bool Network_Port_IPv6_Address_Set(
-    uint32_t object_instance, uint8_t *ip_address)
+    uint32_t object_instance, const uint8_t *ip_address)
 {
     unsigned index = 0; /* offset from instance lookup */
     bool status = false;
@@ -2437,7 +2437,7 @@ bool Network_Port_IPv6_Gateway(
  * @return  true if ip-address was set
  */
 bool Network_Port_IPv6_Gateway_Set(
-    uint32_t object_instance, uint8_t *ip_address)
+    uint32_t object_instance, const uint8_t *ip_address)
 {
     unsigned index = 0; /* offset from instance lookup */
     bool status = false;
@@ -2529,7 +2529,7 @@ static int Network_Port_IPv6_DNS_Server_Encode(
  * @return  true if ip-address was set
  */
 bool Network_Port_IPv6_DNS_Server_Set(
-    uint32_t object_instance, unsigned dns_index, uint8_t *ip_address)
+    uint32_t object_instance, unsigned dns_index, const uint8_t *ip_address)
 {
     unsigned index = 0; /* offset from instance lookup */
     bool status = false;
@@ -2588,7 +2588,7 @@ bool Network_Port_IPv6_Multicast_Address(
  * @return  true if ip-address was set
  */
 bool Network_Port_IPv6_Multicast_Address_Set(
-    uint32_t object_instance, uint8_t *ip_address)
+    uint32_t object_instance, const uint8_t *ip_address)
 {
     unsigned index = 0; /* offset from instance lookup */
     bool status = false;
@@ -2646,7 +2646,7 @@ bool Network_Port_IPv6_DHCP_Server(
  * @return  true if ip-address was set
  */
 bool Network_Port_IPv6_DHCP_Server_Set(
-    uint32_t object_instance, uint8_t *ip_address)
+    uint32_t object_instance, const uint8_t *ip_address)
 {
     unsigned index = 0; /* offset from instance lookup */
     bool status = false;
@@ -2837,7 +2837,7 @@ bool Network_Port_IPv6_Gateway_Zone_Index_Set(
  */
 static bool Network_Port_FD_BBMD_Address_Write(
     uint32_t object_instance,
-    BACNET_HOST_N_PORT *value,
+    const BACNET_HOST_N_PORT *value,
     BACNET_ERROR_CLASS *error_class,
     BACNET_ERROR_CODE *error_code)
 {