drivers: soc: qcom: add initial support for memlat scmi client driver

Add initial support for memlat scmi client driver which registers
into scmi framework for memlat vendor protocol extension.

Also registers with memlat interface driver.

Change-Id: I123944213014a2f61c8df0b1ad822cfde5ff03c4
Signed-off-by: Santosh Mardi <gsantosh@codeaurora.org>