clk: bcm: rpi: Add support for VEC clock

Platform driver clk-bcm2835 gets an inaccurate clock for VEC (107MHz).
Export VEC clock trough clk-raspberrypi which uses the right PLL to
get an accurate 108MHz.

Signed-off-by: Dom Cobley <popcornmix@gmail.com>
[iivanov: Adapted on top of v5.17-rc6]
Signed-off-by: Ivan T. Ivanov <iivanov@suse.de>
Link: https://lore.kernel.org/r/20220829152154.147250-4-iivanov@suse.de


Signed-off-by: Stephen Boyd <sboyd@kernel.org>