Revert "msm: mdss: hdmi: check clk state before power on"

This reverts commit 05f3cbbe
("msm: mdss: hdmi: check clk state before power on"). The check
for clock state was required for earlier target's fast hot plug
use cases, and uses the clock framework for check for clock rates.
This approach does not work on msmcobalt and causes the power on
sequence for HDMI to fail.

CRs-Fixed: 1022772
Change-Id: I320427f810fd35b11335685bae95b3c5fb9c8fee
Signed-off-by: Tatenda Chipeperekwa <tatendac@codeaurora.org>