soc: qcom: Add Type-C alternate mode driver

The Type-C standard defines various "alternate (alt) modes" which enable
standard Type-C connectors to carry non-USB signals and data.

This driver provides an interface for Type-C alternate mode clients to
receive data such as Pin Assignment Notifications from the Type-C stack
running on a remote subsystem (e.g. DSP) via the PMIC GLINK interface.

Change-Id: Ic7eacb6901830cab181d91a1775cf02cddbccae2
Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>