Enable LOG_MIN_PDELAY_REQ_INTERVAL management request

Why don't you enable LOG_MIN_PDELAY_REQ_INTERVAL management request?
phc2sys: add help messages for -l, -m and -q

This patch adds help messages for -l, -m and -q options.
Also it swaps -h for -v because ptp4l's help is this order.

Signed-off-by: Ken ICHIKAWA <ichikawa.ken@jp.fujitsu.com>