usb: gadget: tegra:change condition for vbus check

usb: gadget: tegra:change condition for vbus check

Changing the condition for vbus check. VBUS will be
present when OTG cable is connected, hence vbus
status will be reflected wrong. Correct status
is tracked through vbus_active variable.

Bug 1158853

Change-Id: Ic904beb5919ddafef5becf39ddac1767cdda79cd
Signed-off-by: Rakesh Bodla <rbodla@nvidia.com>
Reviewed-on: http://git-master/r/145148
Reviewed-by: Mrutyunjay Sawant <msawant@nvidia.com>
Tested-by: Mrutyunjay Sawant <msawant@nvidia.com>
Rebase-Id: R0e755cf7ba63041c80ffae32164467ea8f275ce5