xfs: add test results for Linus' small read optimization

Linus posted a possible solution to help performance with
small reads, these are the test results. Essentially we fail
on two tests:

generic/095
generic/741

generic/095 10s ... - output mismatch (see /var/lib/xfstests/results/sr-xfs-reflink-4k/6.9.0-rc6+/xfs_reflink_4k/generic/095.out.bad)
    --- tests/generic/095.out   2024-05-13 13:43:38.491693732 -0700
    +++ /var/lib/xfstests/results/sr-xfs-reflink-4k/6.9.0-rc6+/xfs_reflink_4k/generic/095.out.bad       2024-05-14 00:26:41.560513625 -0700
    @@ -1,2 +1,7 @@
     QA output created by 095
    +fio: first I/O failed. If /media/scratch/file1 is a zoned block device, consider --zonemode=zbd
    +fio: first I/O failed. If /media/scratch/file1 is a zoned block device, consider --zonemode=zbd

generic/741       - output mismatch (see /var/lib/xfstests/results/sr-xfs-reflink-4k/6.9.0-rc6+/xfs_reflink_4k/generic/741.out.bad)
    --- tests/generic/741.out   2024-05-13 13:43:48.905900478 -0700
    +++ /var/lib/xfstests/results/sr-xfs-reflink-4k/6.9.0-rc6+/xfs_reflink_4k/generic/741.out.bad       2024-05-14 03:26:14.599188798 -0700
    @@ -1,3 +1,3 @@
     QA output created by 741
    -mount: TEST_DIR/extra_mnt: SCRATCH_DEV already mounted or mount point busy
    -mount: TEST_DIR/extra_mnt: SCRATCH_DEV already mounted or mount point busy
    +mount: SCRATCH_DEV: Can't open blockdev
    +mount: SCRATCH_DEV: Can't open blockdev

Folks wanting to reproduce can use:

make defconfig-xfs_reflink_4k KDEVOPS_HOSTS_PREFIX=hacks B4_MESSAGE_ID=20240514084221.3664475-1-mcgrof@kernel.org
make -j $(nproc)
make bringup
make fstests
make linux
make fstests-baseline

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>