Propagate BUILD_BFLOAT16 to CFLAGS

Author: martin-frbg

cmake/system.cmake

@@ -469,6 +469,9 @@ endif()
 if (BUILD_COMPLEX16)
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DBUILD_COMPLEX16")
 endif()
+if (BUILD_BFLOAT16)
+       set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DBUILD_BFLOAT16")
+endif()
 if(NOT MSVC)
 set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} ${CCOMMON_OPT}")
 endif()