qpnp-smb2: handle shorted vbus and cc lines and legacy cables

There could be cables where vbus and cc lines are shorted or connected
using a small resistor. Raising VBUS to higher values could cause CC
line to get damaged. CC line cannot tolerate a voltage higher than 6V.

So if such a cable is seen, prevent pd stack from running so there is no
opportunity to increase vbus by selecting a higher voltage profile. Also
disable HVDP too.

Also, prevent PD_ALLOWED if a legacy cable is seen - the spec mentions
that if VBUS is seen along with CC, the adapter is not pd capable.

Change-Id: I7411bd541ffe704dda97dd869a3dbd4dbfc99518
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>