drm/imagination: pvr_device_process_active_queues now static

drm/imagination: pvr_device_process_active_queues now static

The function below is used only within this source file, but is not static.

>> drivers/gpu/drm/imagination/pvr_device.c:129:6: warning: no previous prototype for function 'pvr_device_process_active_queues' [-Wmissing-prototypes]
     129 | void pvr_device_process_active_queues(struct pvr_device *pvr_dev)
         |      ^
   drivers/gpu/drm/imagination/pvr_device.c:129:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     129 | void pvr_device_process_active_queues(struct pvr_device *pvr_dev)
         | ^
         | static
   1 warning generated.

Make it static.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311250632.giVEx7MU-lkp@intel.com/
Fixes: eaf01ee5ba28 ("drm/imagination: Implement job submission and scheduling")
Signed-off-by: Donald Robson <donald.robson@imgtec.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231130160017.259902-3-donald.robson@imgtec.com