Simplify the way the end of a singly linked list is followed (for adding

items), so it is more obvious that we aren't going to indirect through
a NULL pointer.

PR:		144723
Submitted by:	Garrett Cooper <yaneurabeya at gmail.com>
Obtained from:	NetBSD r1.19
MFC after:	2 weeks

usr.bin/hexdump/parse.c

@@ -210,21 +210,18 @@ rewrite(FS *fs)
 	int nconv, prec;
 	size_t len;
 
-	nextpr = NULL;
 	prec = 0;
 
 	for (fu = fs->nextfu; fu; fu = fu->nextfu) {
 		/*
 		 * Break each format unit into print units; each conversion
 		 * character gets its own.
 		 */
+		nextpr = &fu->nextpr;
 		for (nconv = 0, fmtp = fu->fmt; *fmtp; nextpr = &pr->nextpr) {
 			if ((pr = calloc(1, sizeof(PR))) == NULL)
 				err(1, NULL);
-			if (!fu->nextpr)
-				fu->nextpr = pr;
-			else
-				*nextpr = pr;
+			*nextpr = pr;
 
 			/* Skip preceding text and up to the next % sign. */
 			for (p1 = fmtp; *p1 && *p1 != '%'; ++p1);