Backport another MacOSX build fix

patches/openwrt/0011-firmware-utils-remove-dependency-on-error.h-in-tplink-safeloader.patch

+From: Matthias Schiffer <mschiffer@universe-factory.net>
+Date: Sun, 11 Jan 2015 09:14:34 +0100
+Subject: firmware-utils: remove dependency on error.h in tplink-safeloader
+
+Fixes build on Mac OS X
+
+Signed-off-by: Felix Fietkau <nbd@openwrt.org>
+
+diff --git a/tools/firmware-utils/src/tplink-safeloader.c b/tools/firmware-utils/src/tplink-safeloader.c
+index 23d703f..9c5bb54 100644
+--- a/tools/firmware-utils/src/tplink-safeloader.c
++++ b/tools/firmware-utils/src/tplink-safeloader.c
+@@ -34,7 +34,6 @@
+ 
+ #include <assert.h>
+ #include <errno.h>
+-#include <error.h>
+ #include <stdbool.h>
+ #include <stdio.h>
+ #include <stdint.h>
+@@ -143,6 +142,14 @@ static const unsigned char cpe510_support_list[] =
+ 	"CPE220(TP-LINK|UN|N300-2):1.0\r\n"
+ 	"\r\n\xff";
+ 
++#define error(_ret, _errno, _str, ...)				\
++	do {							\
++		fprintf(stderr, _str ": %s\n", ## __VA_ARGS__,	\
++			strerror(_errno));			\
++		if (_ret)					\
++			exit(_ret);				\
++	} while (0)
++
+ 
+ /** Allocates a new image partition */
+ struct image_partition_entry alloc_image_partition(const char *name, size_t len) {
+@@ -200,6 +207,7 @@ struct image_partition_entry make_soft_version(uint32_t rev) {
+ 	struct soft_version *s = (struct soft_version *)entry.data;
+ 
+ 	time_t t;
++
+ 	if (time(&t) == (time_t)(-1))
+ 		error(1, errno, "time");
+