fix: [Common] build failed with VS2015

The current BaseTools aligned with edk2-stable202311
introduces the replacement of __FUNCTION__ with __func__,
which causes compiler failure if the toolchain is using
VS2015. It is because VS2015 doesn't support __func__.
This patch reverts the change and its checker to continue
the VS2015 support.

Reference commit IDs from edk2 repo: b17a3a1 and c9fb11f

Test command: python BuildLoader.py build xxxx -t VS2015

Signed-off-by: Vincent Chen <vincent.chen@intel.com>

BaseTools/Scripts/PatchCheck.py

@@ -504,11 +504,11 @@ class GitDiffCheck:
                                   'but DEBUG_' + mo.group(1) +
                                   ' is now recommended', line)
 
-        rp_file = os.path.realpath(self.filename)
-        rp_script = os.path.realpath(__file__)
-        if line.find('__FUNCTION__') != -1 and rp_file != rp_script:
-            self.added_line_error('__FUNCTION__ was used, but __func__ '
-                                  'is now recommended', line)
+        #rp_file = os.path.realpath(self.filename)
+        #rp_script = os.path.realpath(__file__)
+        #if line.find('__FUNCTION__') != -1 and rp_file != rp_script:
+        #    self.added_line_error('__FUNCTION__ was used, but __func__ '
+        #                          'is now recommended', line)
 
     split_diff_re = re.compile(r'''
                                    (?P<cmd>

MdePkg/Library/BaseLib/SafeString.c

@@ -17,7 +17,7 @@
     if (!(Expression)) { \
       DEBUG ((DEBUG_VERBOSE, \
         "%a(%d) %a: SAFE_STRING_CONSTRAINT_CHECK(%a) failed.  Return %r\n", \
-        __FILE__, DEBUG_LINE_NUMBER, __func__, DEBUG_EXPRESSION_STRING (Expression), Status)); \
+        __FILE__, DEBUG_LINE_NUMBER, __FUNCTION__, DEBUG_EXPRESSION_STRING (Expression), Status)); \
       return Status; \
     } \
   } while (FALSE)