xfs: remove kmem_zone typedef

mainline inclusion
from mainline-v5.15-rc4
commit e7720afa
category: bugfix
bugzilla: 188883, https://gitee.com/openeuler/kernel/issues/I76JSK
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e7720afad068a6729d9cd3aaa08212f2f5a7ceff



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Remove these typedefs by referencing kmem_cache directly.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>

Conflicts: fs/xfs/libxfs/xfs_alloc_btree.c
      fs/xfs/libxfs/xfs_bmap_btree.c
      fs/xfs/libxfs/xfs_btree.h
      fs/xfs/libxfs/xfs_ialloc_btree.c
      fs/xfs/libxfs/xfs_refcount_btree.c
      fs/xfs/libxfs/xfs_rmap_btree.c
Signed-off-by: Long Li <leo.lilong@huawei.com>