seco-mx8m[m|p]: Move VIDEO_PLL1 ssc to own function, enable from spl.
We had this in a general pll enable function. Now with a seperate function it is possible to enable/disable depending on module type and PCN revision. Disable for Trizeps8mini V2R2 and later, as the used mipi2lvds converter uses an external clock, that has to jitter if needed instead.