clk: qcom: gcc-sdxpoorwills: Remove clock flags for RCGs

Remove the clock flag which would try to propagate the rate to the
fixed clock sources of the RCG.

Also fix the cpuss and rbcpr clocks to vote on active only clock of XO and
voltage regulator.

Change-Id: I34278e151cd0bc59ca1d258bea49694f22fdd7f1
Signed-off-by: Taniya Das <tdas@codeaurora.org>