usb: common: otg-fsm: add HNP polling support

Adds HNP polling timer when transits to host state, the OTG status
request will be sent to peripheral after timeout, if host request flag
is set, it will switch to peripheral state, otherwise it will repeat HNP
polling every 1.5s and maintain the current session.

Acked-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>