LU-16350 ldiskfs: removed unused ldiskfs patch

LU-16350 ldiskfs: removed unused ldiskfs patch

The ldiskfs patch:
   linux-5.18/ext4-prealloc.patch
is not used removed it.

Test-Parameters: trivial
HPE-bug-id: LUS-11376
Signed-off-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Change-Id: I628c05681366c937a2a60f1b731c4c628720a8f9
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/55637
Tested-by: Maloo <maloo@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>