10l: Really accept both one and two dashes.

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@18533 b3059339-0415-0410-9bf9-f77b7e298cf2

TOOLS/mphelp_check.py

@@ -56,7 +56,7 @@ if len(sys.argv) < 3:
     sys.exit(1)
 i = 1
 show_missing = False
-if sys.argv[i] == ( '--missing' or '-missing' ):
+if sys.argv[i] in ( '--missing', '-missing' ):
     show_missing = True
     i = 2
 base = parse(sys.argv[i])