util/nvmutil: only set mac_updated at the end

after setting the checksum too

this is functionally no different, but setting it
at the start didn't sit right with me.

it's more logically correct to set it at the end,
in case any error did not result in an exit.

Signed-off-by: Leah Rowe <leah@libreboot.org>

util/nvmutil/nvmutil.c

@@ -268,7 +268,6 @@ cmd_setmac(void)
 	for (int partnum = 0; partnum < 2; partnum++) {
 		if (!goodChecksum(part = partnum))
 			continue;
-		mac_updated = 1;
 
 		for (int w = 0; w < 3; w++) /* write MAC to gbe part */
 			setWord(w, partnum, mac[w]);
@@ -277,6 +276,7 @@ cmd_setmac(void)
 		macf(partnum);
 
 		cmd_setchecksum(); /* MAC updated; need valid checksum */
+		mac_updated = 1;
 	}
 
 	if (mac_updated)