clk: qcom: clk-rpmh: Add QPIC clock support

The clk-rpmh driver only supports on and off RPMh clock resources. Let's
extend the driver by adding support for clocks that are managed by a
different type of RPMh resource known as Bus Clock Manager(BCM). The BCM
is a configurable shared resource aggregator that scales performance
based on a set of frequency points. The QPIC clock is an example of a
resource that is managed by the BCM.

Change-Id: Ib500acaef53b7e17d9864ee509a91693e67dc1e8
Signed-off-by: David Dai <daidavid1@codeaurora.org>