ipsec: ipcomp - Merge IPComp implementations

This patch merges the IPv4/IPv6 IPComp implementations since most
of the code is identical.  As a result future enhancements will no
longer need to be duplicated.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/Makefile b/net/xfrm/Makefile
index 332cfb0..0f439a7 100644
--- a/net/xfrm/Makefile
+++ b/net/xfrm/Makefile
@@ -6,4 +6,5 @@
 		      xfrm_input.o xfrm_output.o xfrm_algo.o
 obj-$(CONFIG_XFRM_STATISTICS) += xfrm_proc.o
 obj-$(CONFIG_XFRM_USER) += xfrm_user.o
+obj-$(CONFIG_XFRM_IPCOMP) += xfrm_ipcomp.o