Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2020-07-28' into staging

Block patches for 5.1.0:
- Fix block I/O for split transfers
- Fix iotest 197 for non-qcow2 formats

# gpg: Signature made Tue 28 Jul 2020 14:45:28 BST
# gpg:                using RSA key 91BEB60A30DB3E8857D11829F407DB0061D5CF40
# gpg:                issuer "mreitz@redhat.com"
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>" [full]
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* remotes/maxreitz/tags/pull-block-2020-07-28:
  iotests/197: Fix for non-qcow2 formats
  iotests/028: Add test for cross-base-EOF reads
  block: Fix bdrv_aligned_p*v() for qiov_offset != 0

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>