nvme-cli: Support for hugetlbfs

nvme-cli: Support for hugetlbfs

Some commands require exceptionally large data transfers, and the
kernel driver supports only a limited number of phyiscal segments per
command. To help support this, try to allocate physically contiguous
space via hugetlbfs and fallback to a normal malloc if that fails.

Rather than deal with the nuances of allocating huge pages, use
libhugetlbfs as a dependency.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Keith Busch <kbusch@kernel.org>