Merge remote-tracking branch 'remotes/nvme/tags/nvme-fixes-20210412-pull-request...

emulated nvme docs and fixes for -rc3

- documentation
- fixes

# gpg: Signature made Mon 12 Apr 2021 07:56:09 BST
# gpg:                using RSA key 522833AA75E2DCE6A24766C04DE1AF316D4F0DE9
# gpg: Good signature from "Klaus Jensen <its@irrelevant.dk>" [unknown]
# gpg:                 aka "Klaus Jensen <k.jensen@samsung.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: DDCA 4D9C 9EF9 31CC 3468  4272 63D5 6FC5 E55D A838
#      Subkey fingerprint: 5228 33AA 75E2 DCE6 A247  66C0 4DE1 AF31 6D4F 0DE9

* remotes/nvme/tags/nvme-fixes-20210412-pull-request:
  hw/block/nvme: drain namespaces on sq deletion
  hw/block/nvme: store aiocb in compare
  hw/block/nvme: map prp fix if prp2 contains non-zero offset
  docs: add nvme emulation documentation

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