drm/msm/hdmi: rename hpd_clks to pwr_clks

drm/msm/hdmi: rename hpd_clks to pwr_clks

As these clocks are now used in the runtime PM callbacks, they have no
connection to 'HPD'. Rename corresponding fields to follow clocks
purpose, to power up the HDMI controller.

Reviewed-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/651720/
Link: https://lore.kernel.org/r/20250505-fd-hdmi-hpd-v5-10-48541f76318c@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>