Revert "[tools] fix the issue of cc detection failure in Windows (RT-Thread#8914)"

This reverts commit 73153ac.

Author: mysterywolf

Diff for: tools/building.py

@@ -195,7 +195,7 @@ def PrepareBuilding(env, root_directory, has_libcpu=False, remove_components = [
         os.environ['RTT_CC_PREFIX'] = exec_prefix
 
     # auto change the 'RTT_EXEC_PATH' when 'rtconfig.EXEC_PATH' get failed
-    if not utils.CmdExists(os.path.join(rtconfig.EXEC_PATH, rtconfig.CC)):
+    if not os.path.exists(os.path.join(rtconfig.EXEC_PATH, rtconfig.CC)):
         if 'RTT_EXEC_PATH' in os.environ:
             # del the 'RTT_EXEC_PATH' and using the 'EXEC_PATH' setting on rtconfig.py
             del os.environ['RTT_EXEC_PATH']

Diff for: tools/utils.py

@@ -309,23 +309,3 @@ def VerTuple(version_str):
     ver = tuple(int(part) for part in ver_parts)
 
     return ver
-
-def CmdExists(cmd):
-    import platform
-
-    cmd_list = cmd.split(' ')
-    cmd = cmd_list[0]
-    if os.path.isfile(cmd):
-        return True
-    else:
-        # check cmd(.exe|.bat|.ps1) under Windows
-        if platform.system() == 'Windows':
-            if cmd.find('exe') != -1 or cmd.find('bat') != -1 or cmd.find('ps1') != -1:
-                return False
-
-            # add .exe then check whether the cmd exists
-            cmd = cmd + '.exe'
-            if os.path.isfile(cmd):
-                return True
-
-        return False