coda: fix fs/coda/sysctl.c build warnings when !CONFIG_SYSCTL

Fix
fs/coda/sysctl.c:14: warning: 'fs_table_header' defined but not used
fs/coda/sysctl.c:44: warning: 'fs_table' defined but not used

these are only used when CONFIG_SYSCTL is defined.

Signed-off-by: Richard A. Holden III <aciddeath@gmail.com>
Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>