add ra2a1 ek

also make some other changes

tools/cmake/cpu/cortex-m23.cmake

@@ -0,0 +1,17 @@
+if (TOOLCHAIN STREQUAL "gcc")
+  set(TOOLCHAIN_COMMON_FLAGS
+    -mthumb
+    -mcpu=cortex-m23
+    -mfloat-abi=soft
+    )
+
+  set(FREERTOS_PORT GCC_ARM_CM0 CACHE INTERNAL "")
+
+elseif (TOOLCHAIN STREQUAL "iar")
+  set(TOOLCHAIN_COMMON_FLAGS
+    --cpu cortex-m23
+    )
+
+  set(FREERTOS_PORT IAR_ARM_CM0 CACHE INTERNAL "")
+
+endif ()