drm/rockchip: vop2: Improve display modes handling on RK3588 HDMI1

drm/rockchip: vop2: Improve display modes handling on RK3588 HDMI1

The RK3588 specific implementation is currently quite limited in terms
of handling the full range of display modes supported by the connected
screens, e.g. 2560x1440@75Hz, 2048x1152@60Hz, 1024x768@60Hz are just a
few of them.

Additionally, it doesn't cope well with non-integer refresh rates like
59.94, 29.97, 23.98, etc.

Make use of HDMI1 PHY PLL as a more accurate DCLK source to handle
all display modes up to 4K@60Hz.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20250223-vop2-hdmi1-disp-modes-v2-1-f4cec5e06fbe@collabora.com