BaseTools: Fix Python SyntaxWarning

- Windows paths must be escaped
- Regex should use raw strings

Signed-off-by: Tim Crawford <tcrawford@system76.com>

BaseTools/Source/Python/Common/GlobalData.py

@@ -54,7 +54,7 @@ gHexPattern = re.compile(r'0[xX]{}+'.format(_HexChar))
 gHexPatternAll = re.compile(r'0[xX]{}+$'.format(_HexChar))
 
 ## Regular expressions for string identifier checking
-gIdentifierPattern = re.compile('^[a-zA-Z][a-zA-Z0-9_]*$', re.UNICODE)
+gIdentifierPattern = re.compile(r'^[a-zA-Z][a-zA-Z0-9_]*$', re.UNICODE)
 ## Regular expression for GUID c structure format
 _GuidCFormatPattern = r"{{\s*0[xX]{Hex}{{1,8}}\s*,\s*0[xX]{Hex}{{1,4}}\s*,\s*0[xX]{Hex}{{1,4}}" \
                       r"\s*,\s*{{\s*0[xX]{Hex}{{1,2}}\s*,\s*0[xX]{Hex}{{1,2}}" \

BaseTools/Source/Python/Common/Misc.py

@@ -1926,4 +1926,4 @@ def CopyDict(ori_dict):
 # Remove the c/c++ comments: // and /* */
 #
 def RemoveCComments(ctext):
-    return re.sub('//.*?\n|/\\*.*?\\*/', '\n', ctext, flags=re.S)
+    return re.sub(r'//.*?\n|/\\*.*?\\*/', '\n', ctext, flags=re.S)

BaseTools/Source/Python/Common/StringUtils.py

@@ -21,7 +21,7 @@ from CommonDataClass.Exceptions import *
 from Common.LongFilePathSupport import OpenLongFilePath as open
 from Common.MultipleWorkspace import MultipleWorkspace as mws
 
-gHexVerPatt = re.compile('0x[a-f0-9]{4}[a-f0-9]{4}$', re.IGNORECASE)
+gHexVerPatt = re.compile(r'0x[a-f0-9]{4}[a-f0-9]{4}$', re.IGNORECASE)
 gHumanReadableVerPatt = re.compile(r'([1-9][0-9]*|0)\.[0-9]{1,2}$')
 
 ## GetSplitValueList