Fixed MacOS specific usage during FreeBSD 11.4 build (#745)

* Fixed path of exports header in BSD ports. 

* Fixed MacOS specific include in BSD ports. 

* Fixed MacOS specific IOSSIOSPEED and IOSSDATALAT usage in BSD ports

ports/bsd/rs485.c

@@ -42,8 +42,11 @@
 
 #include "dlmstp_bsd.h"
 
-/*macOS-darwin includes*/
+#if defined(__APPLE__) || defined(__darwin__)
 #include <IOKit/serial/ioss.h>
+#else
+#include <sys/serial.h>
+#endif
 
 /* Posix serial programming reference:
 https://www.msweet.org/serial/serial.html
@@ -716,6 +719,8 @@ static int openSerialPort(const char *const bsdPath)
     options.c_cflag &= ~CSTOPB; /* 1 Stop Bit */
     options.c_cflag &= ~CSIZE;
     options.c_cflag |= CS8; /* Use 8 bit words */
+
+#if defined(__APPLE__) || defined(__darwin__)
     /* The IOSSIOSPEED ioctl can be used to set arbitrary baud rates other than
      * those specified by POSIX. The driver for the underlying serial hardware
      * ultimately determines which baud rates can be used. This ioctl sets both
@@ -726,6 +731,7 @@ static int openSerialPort(const char *const bsdPath)
         printf("Error calling ioctl(..., IOSSIOSPEED, ...) %s - %s(%d).\n",
             bsdPath, strerror(errno), errno);
     }
+#endif
 
     /* Print the new input and output baud rates. Note that the IOSSIOSPEED
        ioctl interacts with the serial driver directly, bypassing the termios
@@ -778,6 +784,7 @@ static int openSerialPort(const char *const bsdPath)
 
     printf("Handshake lines currently set to %d\n", handshake);
 
+#if defined(__APPLE__) || defined(__darwin__)
     unsigned long mics = 1UL;
 
     /* Set the receive latency in microseconds. Serial drivers use this value to
@@ -793,6 +800,7 @@ static int openSerialPort(const char *const bsdPath)
             strerror(errno), errno);
         goto error;
     }
+#endif
 
     /* Success */
     return fileDescriptor;

ports/bsd/rs485.h

@@ -12,7 +12,7 @@
 #define RS485_H
 
 #include <stdint.h>
-#include "bacnet/bacnet_stack_exports.h"
+#include "bacnet/basic/sys/bacnet_stack_exports.h"
 #include "bacnet/datalink/mstp.h"
 
 #ifdef __cplusplus