xfs: use wait queues directly for the log wait queues

The log grant queues are one of the few places left using sv_t
constructs for waiting. Given we are touching this code, we should
convert them to plain wait queues. While there, convert all the
other sv_t users in the log code as well.

Seeing as this removes the last users of the sv_t type, remove the
header file defining the wrapper and the fragments that still
reference it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/linux-2.6/xfs_linux.h

@@ -37,7 +37,6 @@
 
 #include <kmem.h>
 #include <mrlock.h>
-#include <sv.h>
 #include <time.h>
 
 #include <support/debug.h>