gfs2: move msleep to sleepable context

This patch moves the msleep_interruptible() out of the non-sleepable
context by moving the ls->ls_recover_spin spinlock around so
msleep_interruptible() will be called in a sleepable context.

Cc: stable@vger.kernel.org
Fixes: 4a772772 ("GFS2: Fix recovery issues for spectators")
Suggested-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>