vxlan: remove unused including <linux/version.h>

Remove including <linux/version.h> that don't need it.

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/vxlan.c

@@ -28,7 +28,6 @@
 #include <linux/igmp.h>
 #include <linux/etherdevice.h>
 #include <linux/if_ether.h>
-#include <linux/version.h>
 #include <linux/hash.h>
 #include <net/ip.h>
 #include <net/icmp.h>