udf: Fix preallocation discarding at indirect extent boundary

stable inclusion
from stable-v5.10.161
commit 1a075f4a549481ce6e8518d8379f193ccec6b746
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7P7OH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1a075f4a549481ce6e8518d8379f193ccec6b746



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commit cfe4c1b2 upstream.

When preallocation extent is the first one in the extent block, the
code would corrupt extent tree header instead. Fix the problem and use
udf_delete_aext() for deleting extent to avoid some code duplication.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>