btrfs/319: make the test work when compression is used

btrfs/319: make the test work when compression is used

Currently btrfs/319 assumes there is no compression and that the files
get a single extent (1 fiemap line) with a size of 1048581 bytes. However
when testing with compression, for example by passing "-o compress" to
MOUNT_OPTIONS environment variable, we get several extents and two lines
of fiemap output, which makes the test fail since it hardcodes the fiemap
output:

  $ MOUNT_OPTIONS="-o compress" ./check btrfs/319
  FSTYP         -- btrfs
  PLATFORM      -- Linux/x86_64 debian0 6.11.0-rc6-btrfs-next-173+ #1 SMP PREEMPT_DYNAMIC Tue Sep  3 17:40:24 WEST 2024
  MKFS_OPTIONS  -- /dev/sdc
  MOUNT_OPTIONS -- -o compress /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

  btrfs/319 1s ... - output mismatch (see /home/fdmanana/git/hub/xfstests/results//btrfs/319.out.bad)
      --- tests/btrfs/319.out	2024-08-12 14:16:55.653383284 +0100
      +++ /home/fdmanana/git/hub/xfstests/results//btrfs/319.out.bad	2024-09-05 15:24:53.323076548 +0100
      @@ -6,11 +6,13 @@
       e61178ee0288ebe3fa36a3c975b02c94  SCRATCH_MNT/snap/foo
       e61178ee0288ebe3fa36a3c975b02c94  SCRATCH_MNT/snap/bar
       File bar fiemap in the original filesystem:
      -0: [0..2055]: shared|last
      +0: [0..2047]: shared
      +1: [2048..2055]: shared|last
       Creating a new filesystem to receive the send stream...
      ...
      (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/btrfs/319.out /home/fdmanana/git/hub/xfstests/results//btrfs/319.out.bad'  to see the entire diff)

  HINT: You _MAY_ be missing kernel fix:
        46a6e10a1ab1 btrfs: send: allow cloning non-aligned extent if it ends at i_size

  Ran: btrfs/319
  Failures: btrfs/319
  Failed 1 of 1 tests

So change the test to not rely on the fiemap output in its golden output
and instead just check if all the extents reported by fiemap have the
shared flag set (failing if there are any without the shared flag).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Zorro Lang <zlang@kernel.org>