clk: msm: gdsc: Check gdsc state before disabling the root clock

The regulator framework uses the is_enabled callback to decide
if the gdsc is on/off. In the case of the mmagic gdscs, since
they are left enabled before kernel boot, this call returns
true even though HLOS hasnt voted for the gdscs itself. This
leads to the next call to disable the gdsc to pass though the
regulator framework. The core clock is disabled in the gdsc
code having assumed that it was enabled during the gdsc enable
call which in reality never happened. This leads to falsely
turning off the core clock. Make a change to disable the clock
only if gdsc_enable was called prior to gdsc_disable.
In addition, make separate voter clocks for the mmssnoc_axi
RPM resource to differentiate between the GDSC driver and the
other clients using it.

Change-Id: Ibda44ca92f7d16027dcc8f757b3d755b3cebbb3c
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>