git-completion.bash: extract from else in _git_stash()

To save a level of indentation, perform an early return in the "if" arm
so we can move the "else" code out of the block.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/completion/git-completion.bash

@@ -3035,7 +3035,9 @@ _git_stash ()
 			fi
 			;;
 		esac
-	else
+		return
+	fi
+
 	case "$subcommand,$cur" in
 	push,--*)
 		__gitcomp "$save_opts --message"
@@ -3072,7 +3074,6 @@ _git_stash ()
 	*)
 		;;
 	esac
-	fi
 }
 
 _git_submodule ()