add cmake for broadcom 64-bit, like 32-bit it compiles but text is only 8 bytes (incorrect)

examples/build_system/cmake/cpu/cortex-a72.cmake

@@ -0,0 +1,17 @@
+if (TOOLCHAIN STREQUAL "gcc")
+	set(TOOLCHAIN_COMMON_FLAGS
+		-mcpu=cortex-a72
+		)
+	# set(FREERTOS_PORT GCC_ARM_CM0 CACHE INTERNAL "")
+
+elseif (TOOLCHAIN STREQUAL "clang")
+	set(TOOLCHAIN_COMMON_FLAGS
+		--target=arm-none-eabi
+		-mcpu=cortex-a72
+		)
+	#set(FREERTOS_PORT GCC_ARM_CM0 CACHE INTERNAL "")
+
+elseif (TOOLCHAIN STREQUAL "iar")
+	message(FATAL_ERROR "IAR not supported")
+
+endif ()