*: mass renaming of USE_XXXX to IF_XXXX

and SKIP_XXXX to IF_NOT_XXXX - the second one was especially
badly named. It was not skipping anything!

editors/cmp.c

@@ -37,7 +37,7 @@ int cmp_main(int argc UNUSED_PARAM, char **argv)
 {
 	FILE *fp1, *fp2, *outfile = stdout;
 	const char *filename1, *filename2 = "-";
-	USE_DESKTOP(off_t skip1 = 0, skip2 = 0;)
+	IF_DESKTOP(off_t skip1 = 0, skip2 = 0;)
 	off_t char_pos = 0;
 	int line_pos = 1; /* Hopefully won't overflow... */
 	const char *fmt;
@@ -48,8 +48,8 @@ int cmp_main(int argc UNUSED_PARAM, char **argv)
 	xfunc_error_retval = 2;	/* 1 is returned if files are different. */
 
 	opt_complementary = "-1"
-			USE_DESKTOP(":?4")
-			SKIP_DESKTOP(":?2")
+			IF_DESKTOP(":?4")
+			IF_NOT_DESKTOP(":?2")
 			":l--s:s--l";
 	opt = getopt32(argv, opt_chars);
 	argv += optind;