small update to man page (backported)

dmenu.1

@@ -3,12 +3,12 @@
 dmenu \- dynamic menu
 .SH SYNOPSIS
 .B dmenu
-.RB [ \-font <name> ]
-.RB [ \-normbg <color> ]
-.RB [ \-normfg <color> ]
-.RB [ \-selbg <color> ]
-.RB [ \-selfg <color> ]
-.RB [ \-t <seconds> ]
+.RB [ \-font " <name>"]
+.RB [ \-normbg " <color>"]
+.RB [ \-normfg " <color>"]
+.RB [ \-selbg " <color>"]
+.RB [ \-selfg " <color>"]
+.RB [ \-t " <seconds>"]
 .RB [ \-v ]
 .SH DESCRIPTION
 .SS Overview