fs: remove bdev_try_to_free_page callback

mainline inclusion
from mainline-5.14-rc1
commit acc6100d
category: bugfix
bugzilla: 50788 https://gitee.com/openeuler/kernel/issues/I4DDEL
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=acc6100d3ffa24bdd2add8ea85fb66811bcce5d4



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After remove the unique user of sop->bdev_try_to_free_page() callback,
we could remove the callback and the corresponding blkdev_releasepage()
at all.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-9-yi.zhang@huawei.com


Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Yang Erkun <yangerkun@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>