[Kernel] Support ARCH data types definitions

include/rtdef.h

@@ -58,6 +58,7 @@ extern "C" {
                                          (RT_SUBVERSION * 100) + RT_REVISION)
 
 /* RT-Thread basic data type definitions */
+#ifndef RT_USING_ARCH_DATA_TYPE
 typedef signed   char                   rt_int8_t;      /**<  8bit integer type */
 typedef signed   short                  rt_int16_t;     /**< 16bit integer type */
 typedef signed   int                    rt_int32_t;     /**< 32bit integer type */
@@ -72,6 +73,7 @@ typedef unsigned long                   rt_uint64_t;    /**< 64bit unsigned inte
 typedef signed long long                rt_int64_t;     /**< 64bit integer type */
 typedef unsigned long long              rt_uint64_t;    /**< 64bit unsigned integer type */
 #endif
+#endif
 
 typedef int                             rt_bool_t;      /**< boolean type */
 typedef long                            rt_base_t;      /**< Nbit CPU related date type */

src/Kconfig

@@ -8,6 +8,15 @@ config RT_NAME_MAX
         Each kernel object, such as thread, timer, semaphore etc, has a name,
         the RT_NAME_MAX is the maximal size of this object name.
 
+config RT_USING_ARCH_DATA_TYPE
+    bool "Use the data types defined in ARCH_CPU"
+    default n
+    help
+        For the data type like, `rt_uint8/int8_t, rt_uint16/int16_t, rt_uint32/int32_t`,
+        BSP can define these basic data types in ARCH_CPU level.
+
+        Please re-define these data types in bsp_project.h file.
+
 config RT_USING_SMP
     bool "Enable SMP(Symmetric multiprocessing)"
     default n