Revert "drm/vc4: hdmi: Enforce the minimum rate at runtime_resume"

This reverts commit ae71ab58.

Commit ae71ab58 ("drm/vc4: hdmi: Enforce the minimum rate at
runtime_resume") was introduced to work around an issue partly due to
the clk-bcm2835 driver on the RaspberryPi0-3.

Since we're not using that driver for our HDMI clocks, we can now revert
it.

Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20230126-rpi-display-fw-clk-cleanup-v1-4-d646ff6fb842@cerno.tech


Signed-off-by: Maxime Ripard <maxime@cerno.tech>