USB: OTG Supplement Revision 2.0 updates

ADP (Attach Detection Protocol) is introduced to detect remote
device presence with out applying power on VBUS.  A-device
performs ADP probing and applies power on VBUS when remote device
is attached.  B-device perform ADP sensing and request session
via SRP when remote device is attached. B-device can claim their
ADP capability in OTG descriptor.

HNP polling is introduced for peripheral device to notify its wish
to become host.  Host device polls (i.e execute GetStatus())
peripheral and suspend the bus when peripheral returns host_request
True.

a_alt_hnp_support feature is obsoleted and a_hnp_support feature is
limited to legacy B-devices i.e compliant to older than Rev 2.0 spec.

Change-Id: I1a3c9d35b5e77282da8a47bafd8bc0cc4e5ae1fa
Signed-off-by: Pavankumar Kondeti <pkondeti@qualcomm.com>