vfs: Use const for kernel parser table

This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.

This was posted for review some time ago and I believe its been in -mm
since then.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Alexander Viro <aviro@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/net/9p/client.c b/net/9p/client.c
index 10e3203..e053e06 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -52,7 +52,7 @@
 	Opt_err,
 };
 
-static match_table_t tokens = {
+static const match_table_t tokens = {
 	{Opt_msize, "msize=%u"},
 	{Opt_legacy, "noextend"},
 	{Opt_trans, "trans=%s"},