msm: mdss: hdmi: update panel power state for all hdmi use cases

Update the panel power state after the HDMI transmitter core is
powered on for all HDMI use cases (external and primary). This
will enable other entities (e.g. Audio driver) to query the correct
power state during boot up.

Change-Id: Ie6765880e9e9d9d6f087c1726d331ef2dd632cad
Signed-off-by: Tatenda Chipeperekwa <tatendac@codeaurora.org>