fix fs/nfs/nfsroot.c compilation

This fixes the following compile error caused by commit
f9247273cb69ba101877e946d2d83044409cc8c5 ("UFS: add const to parser
token table"):

CC fs/nfs/nfsroot.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/nfs/nfsroot.c:130: error: tokens causes a section type conflict
make[3]: *** [fs/nfs/nfsroot.o] Error 1

Signed-off-by: Adrian Bunk <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/nfs/nfsroot.c

···
 	Opt_err
 };
 
-static match_table_t __initdata tokens = {
+static match_table_t __initconst tokens = {
 	{Opt_port, "port=%u"},
 	{Opt_rsize, "rsize=%u"},
 	{Opt_wsize, "wsize=%u"},