sunxi: video: Modify sunxi_lcdc_pll_set to work with both tcon0 and tcon1

sunxi: video: Modify sunxi_lcdc_pll_set to work with both tcon0 and tcon1

Modify sunxi_lcdc_pll_set to work with both tcon0 and tcon1, this is a
preparation patch for adding lcd support.

While at it also swap the divider search order, searching from low to
high, as the comment above the code says we should do. In cases where there
are multiple solutions this will result in picking a lower pll clock and
divider, which is more stable and saves power.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>