msm: adsprpc: remove PM vote counter in fastrpc driver

Remove PM vote counter in the fastrpc driver as the system wakeup
events framework will keep track of CPU awake and relax votes from
a specific client and handle it accordingly.

Change-Id: I827eeffe3aabddbf983ba60e79925febe9410f00
Acked-by: Thyagarajan Venkatanarayanan <venkatan@qti.qualcomm.com>
Signed-off-by: c_mtharu <mtharu@codeaurora.org>