ARM: dts: msm: Fix sleep settings of SPI-USB bridge gpio

If a gpio is active as input (which is the default), then a
floating input with no-pull will consume significantly more
current. Configure the gpio as pull-down in sleep settings.

Change-Id: Ifcdaaf587d2981c9e4c0e565e3307444a47d9656
CRs-Fixed: 658474
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>