ARM: dts: msm: Add measure support ddr clock for SM6150

Add an additional MC_CC debug base to map the mc clock period
register used to calculate the frequency of the MC clock.
Change the name of the measure_only_bimc_clk to better reflect
the name of the clock(memory controller clock controller) we're
trying to measure.

Change-Id: I89c460113567166dd4a58fb04ede0d5a7c9ef6f2
Signed-off-by: Odelu Kukatla <okukatla@codeaurora.org>