i.MX clock changes for 6.16

- Add video PLL clocks to both i.MX8MM and i.MX8MP
  while dropping the numeral suffix.
- Add imx_anatop_get_clk_hw helper
- Add anatop clock providers for i.MX8M[MNP]
- Drop ccm_ prefix from base in i.MX8MP clock provider
- Document bindings for PLLs in imx8m-clock schema

dt-bindings: clock: imx8m-clock: add PLLs

Though adding the PLLs to clocks and clock-names properties will break
the ABI, it is required to accurately describe the hardware. Indeed,
the Clock Control Module (CCM) receives clocks from the PLLs and
oscillators and generates clocks for on-chip peripherals.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250424062154.2999219-17-dario.binacchi@amarulasolutions.com
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>