[IPV4]: Don't select XFRM for ip_gre

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/Kconfig

@@ -252,7 +252,6 @@ config NET_IPIP
 
 config NET_IPGRE
 	tristate "IP: GRE tunnels over IP"
-	select XFRM
 	help
 	  Tunneling means encapsulating data of one protocol type within
 	  another protocol and sending it over a channel that understands the