clk: imx: add i.MX91 clk

Reuse i.MX93 clk driver for i.MX91, because i.MX91 reuses the
Clock Control Module from i.MX93, with only a few clocks removed
and a few clocks added.

For clocks specific to i.MX93 use PLAT_IMX93 to flag them, for
clocks specific to i.MX91, use PLAT_IMX91 to flag them. Others
are shared by both.

Signed-off-by: Pengfei Li <pengfei.li_1@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20241023184651.381265-5-pengfei.li_1@nxp.com


Signed-off-by: Abel Vesa <abel.vesa@linaro.org>