mailbox: cmdq: add multi-gce clocks support for mt8195

For the design of GCE hardware event signal transportation,
evnet rx will send the event signal to all GCE event merges
after receiving the event signal from the other hardware.

Because GCE event merges need to response to event rx, their
clocks must be enabled at that time.

To make sure all the gce clock is enabled while receiving the
hardware event, each cmdq mailbox should enable or disable
the others gce clk at the same time.

Signed-off-by: jason-jh.lin <jason-jh.lin@mediatek.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>