clk: rockchip: rk3568: Mark pclk_usb as critical

clk: rockchip: rk3568: Mark pclk_usb as critical

In the reference manual under "2.8.6 NIU Clock gating reliance"
it is stated that pclk_usb_niu has a dependency on hclk_usb_niu.

While the manual does not state that this is a bi-directional
relationship it was noted that the sdmmc2 failed to operate for me in
mmc mode if the pclk_usb was not marked as critical. The parent clock
of the hclk_sdmmc2 is hclk_usb.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Link: https://lore.kernel.org/r/20231204185719.569021-8-macroalpha82@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>