am: simplify parsing of "--[no-]keep-cr"

Command line options "--keep-cr" and its negation trigger
OPT_SET_INT_F(PARSE_OPT_NONEG) to set a variable to 1 and 0
respectively.  Using OPT_SET_INT() to implement the positive variant
that sets the variable to 1 without specifying PARSE_OPT_NONEG gives
us the negative variant to set it to 0 for free.

Signed-off-by: Junio C Hamano <[email protected]>

Author: gitster

builtin/am.c

@@ -2347,12 +2347,9 @@ int cmd_am(int argc, const char **argv, const char *prefix)
 			N_("pass -b flag to git-mailinfo"), KEEP_NON_PATCH),
 		OPT_BOOL('m', "message-id", &state.message_id,
 			N_("pass -m flag to git-mailinfo")),
-		OPT_SET_INT_F(0, "keep-cr", &keep_cr,
-			N_("pass --keep-cr flag to git-mailsplit for mbox format"),
-			1, PARSE_OPT_NONEG),
-		OPT_SET_INT_F(0, "no-keep-cr", &keep_cr,
-			N_("do not pass --keep-cr flag to git-mailsplit independent of am.keepcr"),
-			0, PARSE_OPT_NONEG),
+		OPT_SET_INT(0, "keep-cr", &keep_cr,
+			    N_("pass --keep-cr flag to git-mailsplit for mbox format"),
+			    1),
 		OPT_BOOL('c', "scissors", &state.scissors,
 			N_("strip everything before a scissors line")),
 		OPT_CALLBACK_F(0, "quoted-cr", &state.quoted_cr, N_("action"),