xen/x86: Fix Syntax warning in gen-cpuid.py

Python 3.12.2 warns:

xen/tools/gen-cpuid.py:50: SyntaxWarning: invalid escape sequence '\s'
  "\s+([\s\d]+\*[\s\d]+\+[\s\d]+)\)"
xen/tools/gen-cpuid.py:51: SyntaxWarning: invalid escape sequence '\s'
  "\s+/\*([\w!]*) .*$")

Specify the strings as raw strings so '\s' is read as literal '\' + 's'.
This avoids escaping all the '\'s in the strings.

Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

xen/tools/gen-cpuid.py

@@ -47,8 +47,8 @@ def parse_definitions(state):
     """
     feat_regex = re.compile(
         r"^XEN_CPUFEATURE\(([A-Z0-9_]+),"
-        "\s+([\s\d]+\*[\s\d]+\+[\s\d]+)\)"
-        "\s+/\*([\w!]*) .*$")
+        r"\s+([\s\d]+\*[\s\d]+\+[\s\d]+)\)"
+        r"\s+/\*([\w!]*) .*$")
 
     word_regex = re.compile(
         r"^/\* .* word (\d*) \*/$")