xfs: relocate the eofb/cowb workqueue functions

mainline-inclusion
from mainline-v5.11-rc4
commit f9296569
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4KIAO
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f9296569837c3fd66ae32717b0f8f5a26758b4b7



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Move the xfs_{eof,cow}blocks_worker and xfs_queue_{eof,cow}blocks
functions further down in the file so that the cleanups in the next
patches won't have to pre-declare static functions.  No functional
changes.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lihong Kou <koulihong@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>