msm: clock-8974: Allow measurement of clocks in the WCNSS

For debugging reasons, it is required that WLAN drivers
be able to measure clocks in the WCNSS subsystem. It is
assumed that the WCNSS debug mux is already programmed
by the WCNSS firmware.

Change-Id: Ia1bc054f8dd8bd51e62046c9ea71624a22bc890e
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>