usb: chipidea: retire flag CI_HDRC_PULLUP_ON_VBUS

Currently, the controller only runs when the ci->vbus_active is true.
So the flag CI_HDRC_PULLUP_ON_VBUS is useless no longer.
If the user doesn't have otgsc, he/she needs to change ci_handle_vbus_change
to update ci->vbus_active.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>