emulated nvme updates

* various fixes (Gollu Appalanaidu)
* refactoring (me)
* move to hw/nvme from hw/block (me)

# gpg: Signature made Mon 17 May 2021 10:16:01 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-next-pull-request:
  hw/nvme: move nvme emulation out of hw/block
  hw/block/nvme: move zoned constraints checks
  hw/block/nvme: remove irrelevant zone resource checks
  hw/block/nvme: remove num_namespaces member
  hw/block/nvme: streamline namespace array indexing
  hw/block/nvme: add metadata offset helper
  hw/block/nvme: cache lba and ms sizes
  hw/block/nvme: replace nvme_ns_status
  hw/block/nvme: remove non-shared defines from header file
  hw/block/nvme: cleanup includes
  hw/block/nvme: consolidate header files
  hw/block/nvme: rename __nvme_select_ns_iocs
  hw/block/nvme: rename __nvme_advance_zone_wp
  hw/block/nvme: rename __nvme_zrm_open
  hw/block/nvme: align with existing style
  hw/block/nvme: function formatting fix
  hw/block/nvme: fix io-command set profile feature
  hw/block/nvme: consider metadata read aio return value in compare
  hw/block/nvme: rename reserved fields declarations
  hw/block/nvme: remove redundant invalid_lba_range trace

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