soc: qcom: Add support for QDSS bridge driver

Add support to route QDSS data received from MDM via MHI
to USB. The driver will help route diag traffic over the
QDSS sub-system to USB on APPS side. It acts as a bridge
between PCIE MHI and USB interface.

Change-Id: Ifa50d4c3ce39e10e928e3e6f3e79085d2bc9d4e6
Signed-off-by: Satyajit Desai <sadesai@codeaurora.org>