bash: add missing format-patch command line options

Signed-off-by: SZEDER Gábor <szeder@ira.uka.de>
Acked-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/completion/git-completion.bash

@@ -838,6 +838,8 @@ _git_format_patch ()
 			--not --all
 			--cover-letter
 			--no-prefix --src-prefix= --dst-prefix=
+			--inline --suffix= --ignore-if-in-upstream
+			--subject-prefix=
 			"
 		return
 		;;