Fix usage of setmode in devfs. it can fail due to malloc, so we should print the
correct error message.  
Index: src/sbin/devfs/rule.c
===================================================================
--- src/sbin/devfs/rule.c	(revision 107)
+++ src/sbin/devfs/rule.c	(revision 108)
@@ -399,9 +399,14 @@
 			if (av[1] == NULL)
 				errx(1, "expecting argument for mode");
 			dr->dr_iacts |= DRA_MODE;
+			errno = 0;
 			set = setmode(av[1]);
-			if (set == NULL)
-				errx(1, "invald mode: %s", av[1]);
+			if (set == NULL) {
+				if (!errno)
+					errx(1, "invald mode: %s", av[1]);
+				else
+					err(1, "setmode");
+			}
 			dr->dr_mode = getmode(set, 0);
 			av += 2;
 		} else if (strcmp(av[0], "include") == 0) {