net: usb: Add support for embedded rmnet usb host driver

Embedded rmnet usb host driver will be used to communicate with modem
devices having rmnet interface. This driver works as pass through layer
for control and data path communication. Driver currently supports device
with product id: 0x9034 and vendor id : 0x05c6.

Change-Id: Ie037af915f2650828420a351bd3fe503a505eaee
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>