Strip tabs and trailing white spaces, and fix end of files (#748)

* format: Strip trailing whitespaces

We want to get rid of trailing whitespaces completly as they make just git
noice. Much better to start using automated tools to get rid of them once and
not getting them back again. This way git history will be cleaner and review
easier.

Commit was generated with:

    pre-commit run --all-files trailing-whitespace

* format: Files should have exactly one new line end of them

It is good practice that every file has one new line. It is not now days so
mandatory but it also is not nice if file has lot of newlines end of it. We will
use pre-commit which takes automatically care about this so let's fix all.

Commit was generated with:

    pre-commit run --all-files end-of-file-fixer

* format: Convert tabs to spaces

Project mostly use spaces over tabs. When mixing tabs and spaces this usually
makes formatting issues and also when changing those in commits it will make lot
of git noise. We will force spaces most of the time and use pre-commit to fix.

Commit was generated with:

    pre-commit run --all-files remove-tabs

---------

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

ports/stm32f10x/CMakeLists.txt

@@ -1,5 +1,5 @@
 # This is a CMake example for STM32 ARM Cortex-M3 STM32F103RGT6 on
-# a STM32 Discovery Kit evaluation board using the ARM GCC compiler 
+# a STM32 Discovery Kit evaluation board using the ARM GCC compiler
 # and STM32 CMSIS library.
 #
 # Board STM32F103 Discovery Kit
@@ -234,13 +234,13 @@ target_compile_definitions(${EXECUTABLE} PRIVATE
 # inhibit pedantic warnings
 target_compile_options(${EXECUTABLE} PRIVATE
     -Wall -Wextra -pedantic
-    -Wfloat-equal -Wconversion -Wredundant-decls 
+    -Wfloat-equal -Wconversion -Wredundant-decls
     -Wswitch-default
     # don't warn about conversion, sign, compares, long long and attributes
     # since they are common in embedded
-    -Wno-sign-conversion 
+    -Wno-sign-conversion
     -Wno-conversion
-    -Wno-sign-compare 
+    -Wno-sign-compare
     -Wno-long-long
     -Wno-attributes
     # don't warn about implicit fallthrough since it is common in network protocols
@@ -296,7 +296,7 @@ add_custom_target(symbols
 )
 
 # calculate the worst case CSTACK memory usage by size and place into a file
-add_custom_target(cstack 
+add_custom_target(cstack
     DEPENDS ${EXECUTABLE}
     COMMENT "Print CSTACK memory depth by size"
     COMMAND ${CMAKE_CSTACK} ${EXECUTABLE} ${CMAKE_CURRENT_BINARY_DIR} 1> ${PROJECT_NAME}.su
@@ -306,7 +306,7 @@ add_custom_target(cstack
 )
 
 # Print file and library sizes
-add_custom_target(memmap 
+add_custom_target(memmap
     DEPENDS ${PROJECT_NAME}.map
     COMMENT "Print file and library memory usage by size"
     COMMAND ${CMAKE_MEMAP} -t GCC_ARM ${PROJECT_NAME}.map