Update outdated gcovr patch

Author: addaleax

gcovr-patches.diff

@@ -21,11 +21,3 @@ index 034779c86d29..e68b239c424f 100755
  if options.root is not None:
      if not options.root:
          sys.stderr.write(
-@@ -2155,6 +2158,7 @@ if options.root is not None:
- else:
-     root_dir = starting_dir
-     options.root_filter = re.compile(re.escape(root_dir + os.sep))
-+    starting_dir = root_dir
- 
- for i in range(0, len(options.filter)):
-     options.filter[i] = re.compile(options.filter[i])