clk: qcom: gcc-sdxpoorwills: Remove MSS clocks support

GCC MSS clocks are controlled by Modem per latest
clock plan. Update GCC driver accordingly.

CRs-Fixed: 2155384
Signed-off-by: Vicky Wallace <vwallace@codeaurora.org>
Change-Id: I24247b76e572f09e44f03c80be316c4d1052f944