[NETFILTER]: Change tunables to __read_mostly

Change some netfilter tunables to __read_mostly.  Also fixed some
incorrect file reference comments while I was in there.

(this will be my last __read_mostly patch unless someone points out
something else that needs it)

Signed-off-by: Brian Haley <brian.haley@hp.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index 4ef8366..9a1de0c 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -428,7 +428,7 @@
 
 /* Sysctl support */
 
-int nf_conntrack_checksum = 1;
+int nf_conntrack_checksum __read_mostly = 1;
 
 #ifdef CONFIG_SYSCTL