clk: qcom: debugcc-sdxlemur: Add mc_cc_debug_mux to gcc parents

The mc_cc_debug_mux is missing from the gcc_debug_mux parent names and
mux selections. This causes read errors from the mc_cc_debug_mux
clk_measure file. Add the missing information.

Change-Id: Ib4b9484a5e5218823f7cc338f1151a01034dccf4
Signed-off-by: Mike Tipton <mdtipton@codeaurora.org>