clk: renesas: r8a779g0: Model PLL1/3/4/6 as fractional PLLs

Currently, all PLLs but PLL2 are modelled as fixed divider clocks, based
on the state of the mode pins.  However, the boot loader stack may have
changed the actual PLL configuration from the default, leading to
incorrect clock frequencies.

Describe PLL1 as a fixed fractional PLL instead, and PLL2, PLL3, PLL4,
and PLL6 as variable fractional PLLs.

Reformat nearby lines to retain a consistent layout.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/b98523ed08de7386944c5ae860eae107dc28be3e.1721648548.git.geert+renesas@glider.be