[scons][iar] 将IAR的PLATFORM字段由iar调整为iccarm

将路径更新为IAR最新版本的路径

bsp/mm32f103x/rtconfig.py

@@ -21,7 +21,7 @@ elif CROSS_TOOL == 'keil':
     PLATFORM = 'armcc'
     EXEC_PATH = 'C:/Keil_v5'
 elif CROSS_TOOL == 'iar':
-    PLATFORM = 'iar'
+    PLATFORM = 'iccarm'
     EXEC_PATH = 'C:/Program Files (x86)/IAR Systems/Embedded Workbench 7.2'
 
 if os.getenv('RTT_EXEC_PATH'):
@@ -86,7 +86,7 @@ elif PLATFORM == 'armcc':
 
     POST_ACTION = 'fromelf --bin $TARGET --output rtthread.bin \nfromelf -z $TARGET'
 
-elif PLATFORM == 'iar':
+elif PLATFORM == 'iccarm':
     # toolchains
     CC = 'iccarm'
     AS = 'iasmarm'