usb: chipidea: otg: remove mutex unlock and lock while stop and start role

usb: chipidea: otg: remove mutex unlock and lock while stop and start role

commit a5a356cee89f86ff86cc3ce24136ca1f802c1bf1 upstream.

Wrongly release mutex lock during otg_statemachine may result in re-enter
otg_statemachine, which is not allowed, we should do next state transtition
after previous one completed.

Fixes: 826cfe751f3e ("usb: chipidea: add OTG fsm operation functions implementation")
Signed-off-by: Li Jun <jun.li@freescale.com>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>