phy: rockchip: samsung-hdptx: Avoid Hz<->hHz unit conversion overhead

The ropll_tmds_cfg table used to identify the configuration params for
the supported rates expects the search key, i.e. bit_rate member of
struct ropll_config, to be provided in hHz rather than Hz (1 hHz = 100
Hz).  This requires multiple conversions between these units being
performed at runtime.

Improve implementation clarity and efficiency by consistently using the
Hz unit throughout driver's internal data structures and functions.
Also rename the rather misleading struct member.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250318-phy-sam-hdptx-bpc-v6-8-8cb1678e7663@collabora.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>