CoreSight: QPDI enhancement for hotplug insertion of debug card

Generally, regulators for SDC slot has to be turned on/off based on the
usage. But for debug requirement the regulators driving the SD card pins
has to be always on which results in lot of power dissipation. Inorder
to avoid this situation, there is a QPDI enhancement where the LDO's
driving the SD card will be on only when we insert the debug card while
pressing the VOL- button.

Change-Id: I4b56e40ee18777ac19ccda8ab4b0575e1cf4dd5c
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>