clk: qcom: gcc-kona: Add clk mux sources for usb pipe clocks

Due to a new requirement for Kona where the USB driver needs to
toggle between bi_tcxo and phy pipe clock as part of its CX
collapse sequence, add pipe_clk_src regmap_mux objects to facilitate
this control.

Change-Id: I6f41fa07297bededf52e58e01e940ae7bd9be918
Signed-off-by: David Dai <daidavid1@codeaurora.org>