hw/nvme: add support for zoned random write area

Add support for TP 4076 ("Zoned Random Write Area"), v2021.08.23
("Ratified").

This adds three new namespace parameters: "zoned.numzrwa" (number of
zrwa resources, i.e. number of zones that can have a zrwa),
"zoned.zrwas" (zrwa size in LBAs), "zoned.zrwafg" (granularity in LBAs
for flushes).

Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>