lsblk: introduce 'MQ' column

lsblk: introduce 'MQ' column

Typically a modern block device supports mutil queues feature, count
queues by walking '$sysfs/mq' directory. If no '$sysfs/mq' exists, it
is a legacy single queue.

~# lsblk --nvme -o NAME,TYPE,MODEL,TRAN,RQ-SIZE,MQ
NAME    TYPE MODEL                      TRAN   RQ-SIZE  MQ
nvme0n1 disk INTEL SSDPF2KX038TZ        nvme      1023 135
nvme3n1 disk INTEL SSDPE2KX020T8        nvme      1023 128
nvme1n1 disk SAMSUNG MZQL23T8HCLS-00A07 nvme      1023 129
nvme2n2 disk RP2A03T8RK004LX            nvme      1023  64
nvme2n3 disk RP2A03T8RK004LX            nvme      1023  64

Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>