xfs: fix memory leak on error in xfs_alloc_zone_info()

xfs: fix memory leak on error in xfs_alloc_zone_info()

Currently, the 0th index of the zi_used_bucket_bitmap array is not freed
on error due to the pre-decrement then evaluate semantic of the while
loop used in xfs_alloc_zone_info(). Fix it by allowing for the i == 0
case to be covered.

Fixes: 080d01c41d44 ("xfs: implement zoned garbage collection")
Cc: stable@vger.kernel.org # v6.15
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>