fs/quota: Remove "select SRCU"

Now that the SRCU Kconfig option is unconditionally selected, there is
no longer any point in selecting it.  Therefore, remove the "select SRCU"
Kconfig statements.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Jan Kara <jack@suse.com>
Acked-by: Jan Kara <jack@suse.cz>
Reviewed-by: John Ogness <john.ogness@linutronix.de>

fs/quota/Kconfig

@@ -6,7 +6,6 @@
 config QUOTA
 	bool "Quota support"
 	select QUOTACTL
-	select SRCU
 	help
 	  If you say Y here, you will be able to set per user limits for disk
 	  usage (also called disk quotas). Currently, it works for the