clk: qcom: gcc: Use floor ops for SDCC clocks

Update global clock controller SDCC2/4 clocks to use the floor rcg ops,
so as to use the rounded down clock rates for these clocks.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
Link: https://lkml.kernel.org/r/20190909074410.18977-1-tdas@codeaurora.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>