Update fs.

external/fs/fs.c

@@ -4915,7 +4915,7 @@ static fs_result fs_mkdir_stdio_win32(const char* pPath)
     int result;
 
     /* If it's a drive letter segment just pretend it's successful. */
-    if (pPath[0] >= 'a' && pPath[0] <= 'z' || pPath[0] >= 'A' && pPath[0] <= 'Z') {
+    if ((pPath[0] >= 'a' && pPath[0] <= 'z') || (pPath[0] >= 'A' && pPath[0] <= 'Z')) {
         if (pPath[1] == ':' && pPath[2] == '\0') {
             return FS_SUCCESS;
         }