Remove C99 requirement from CMake file (#633)

* Remove C99 requirement from CMake file

The kernel source is C89 compliant and does not need C99.

Signed-off-by: Gaurav Aggarwal <[email protected]>

* Explicitly set C89 requirement for kernel

Signed-off-by: Gaurav Aggarwal <[email protected]>

---------

Signed-off-by: Gaurav Aggarwal <[email protected]>

Author: aggarg

CMakeLists.txt

@@ -230,8 +230,7 @@ endif()
 
 ########################################################################
 # Requirements
-set(CMAKE_C_STANDARD 99)
-set(CMAKE_C_STANDARD_REQUIRED ON)
+set_property(TARGET freertos_kernel PROPERTY C_STANDARD 90)
 
 ########################################################################
 # Overall Compile Options