Maildir: flagmatchre --> re_flagmatch

Overlooked a variable renaming when merging in a branch.

Signed-off-by: Sebastian Spaeth <Sebastian@SSpaeth.de>

Changelog.draft.rst

@@ -31,3 +31,5 @@ Bug Fixes
 * Fixed MachineUI to urlencode() output lines again, rather than
   outputting multi-line items. It's ugly as hell, but it had been that
   way for years.
+
+* Fixed Maildir regression "flagmatchre" not found. (regressed in 6.5.0)

offlineimap/folder/Maildir.py

@@ -298,7 +298,7 @@ class MaildirFolder(BaseFolder):
             # Flags have actually changed, construct new filename
             # Strip off existing infostring (preserving small letter flags that
             # dovecot uses)
-            infomatch = self.flagmatchre.search(filename)
+            infomatch = self.re_flagmatch.search(filename)
             if infomatch:
                 filename = filename[:-len(infomatch.group())] #strip off
             infostr = '%s2,%s' % (self.infosep, ''.join(sorted(flags)))