[PATCH ethtool 1/3] misc: Fix build with kernel headers < v4.11

Not all toolchain kernel headers may contain upstream commit
2618be7dccf8739b89e1906b64bd8d551af351e6 ("uapi: fix linux/if.h
userspace compilation errors") which is included in v4.11 and onwards.
Err on the side of caution by including sys/socket.h ahead of including
linux/if.h.

Fixes: 1fa60003a8b8 ("misc: header includes cleanup")
Reported-by: Markus Mayer <mmayer@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 internal.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/internal.h b/internal.h
index b80f77afa4c0..f7aaaf5229f4 100644
--- a/internal.h
+++ b/internal.h

@@ -21,6 +21,7 @@
 #include <unistd.h>
 #include <endian.h>
 #include <sys/ioctl.h>
+#include <sys/socket.h>
 #include <linux/if.h>
 
 #include "json_writer.h"

-- 
2.34.1