clk: qcom: Add Krait clock controller driver

The Krait CPU clocks are made up of a primary mux and secondary
mux for each CPU and the L2, controlled via cp15 accessors. For
Kraits within KPSSv1 each secondary mux accepts a different aux
source, but on KPSSv2 each secondary mux accepts the same aux
source.

Cc: <devicetree@vger.kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Tested-by: Craig Tatlor <ctatlor97@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>