chore: squash previous commits from other branches

examples/build_system/make/cpu/cortex-m55.mk

@@ -0,0 +1,28 @@
+ifeq ($(TOOLCHAIN),gcc)
+  CFLAGS += \
+    -mthumb \
+    -mcpu=cortex-m55 \
+    -mfloat-abi=hard \
+    -mfpu=fpv5-d16 \
+    -mcmse
+
+else ifeq ($(TOOLCHAIN),clang)
+  CFLAGS += \
+	  --target=arm-none-eabi \
+	  -mcpu=cortex-m55 \
+	  -mfpu=fpv5-d16 \
+
+else ifeq ($(TOOLCHAIN),iar)
+  CFLAGS += \
+  	--cpu cortex-m55 \
+  	--fpu VFPv5_D16 \
+
+  ASFLAGS += \
+		--cpu cortex-m55 \
+		--fpu VFPv5_D16 \
+
+else
+  $(error "TOOLCHAIN is not supported")
+endif
+
+FREERTOS_PORTABLE_SRC ?= $(FREERTOS_PORTABLE_PATH)/ARM_CM55_NTZ/non_secure