msm: ipa3: send usb-connect from rndis-ipa

To resolve the timing issue between usb-driver
and android framework, made the change on rndis
ipa to send the usb-connect msg when usb-driver
connect the IPA pipes.

Change-Id: I51de37bc7610cb0a94659c64146f10ed322210b2
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>