MLK-17293-6 cpufreq: imx7ulp: support new set-points

MLK-17293-6 cpufreq: imx7ulp: support new set-points

According to datasheet Rev-D, on B0 part, below CPU
freq needs to be supported:

500MHz for RUN mode;
720MHz for HSRUN mode.

To achieve best accurate frequency for CPU, adjust
SPLL's frequency for SPLL_PFD0 which is CPU's
clock source:

SPLL 528MHz -> SPLL_PFD0 500.2MHz;
SPLL 480MHz -> SPLL_PFD0 720MHz;

Remove CPU RUN/HSRUN mode switch, since it is implemented
as clock mux, whenever clock parent is switched, the
RUN/HSRUN mode will be changed accordingly.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Bai Ping <ping.bai@nxp.com>