lockd: fix FILE_LOCKING=n build error

lockd/svclock.c is missing a header file <linux/fs.h>.

<linux/fs.h> is missing a definition of locks_release_private()
for the config case of FILE_LOCKING=n, causing a build error:

fs/lockd/svclock.c:330: error: implicit declaration of function 'locks_release_private'

lockd without FILE_LOCKING doesn't make sense, so make LOCKD and LOCKD_V4
depend on FILE_LOCKING, and make NFS depend on FILE_LOCKING.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/fs/Kconfig b/fs/Kconfig
index 9f7270f..44ab328 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -226,10 +226,12 @@
 
 config LOCKD
 	tristate
+	depends on FILE_LOCKING
 
 config LOCKD_V4
 	bool
 	depends on NFSD_V3 || NFS_V3
+	depends on FILE_LOCKING
 	default y
 
 config EXPORTFS