[openwrt/openwrt] firmware-utils: fix build on not Linux

[LEDE Commits]

ldir pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/c9faa84b316f74b666884a9524c8e046d0d81d1a

commit c9faa84b316f74b666884a9524c8e046d0d81d1a
Author: Kevin Darbyshire-Bryant <ldir at darbyshire-bryant.me.uk>
AuthorDate: Sat Aug 21 20:08:07 2021 +0100

    firmware-utils: fix build on not Linux
    
    Signed-off-by: Kevin Darbyshire-Bryant <ldir at darbyshire-bryant.me.uk>
---
 tools/firmware-utils/Makefile           | 2 +-
 tools/firmware-utils/src/mkzyxelzldfw.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/firmware-utils/Makefile b/tools/firmware-utils/Makefile
index d7f378d2f3..7b669ac0c6 100644
--- a/tools/firmware-utils/Makefile
+++ b/tools/firmware-utils/Makefile
@@ -7,7 +7,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME := firmware-utils
-PKG_RELEASE := 8
+PKG_RELEASE := 9
 
 include $(INCLUDE_DIR)/host-build.mk
 include $(INCLUDE_DIR)/kernel.mk
diff --git a/tools/firmware-utils/src/mkzyxelzldfw.c b/tools/firmware-utils/src/mkzyxelzldfw.c
index 1b335f8ddc..b61d0c1485 100644
--- a/tools/firmware-utils/src/mkzyxelzldfw.c
+++ b/tools/firmware-utils/src/mkzyxelzldfw.c
@@ -17,7 +17,7 @@
 #include <string.h>
 #include <unistd.h>
 #include <netinet/in.h>
-#include <linux/limits.h>
+#include <limits.h>
 #include "md5.h"
 
 #define ZYXEL_MAGIC	0xdeadbeaf