phy: cadence: Sierra: Replace `clk_register(`) with `clk_hw_register()`

phy: cadence: Sierra: Replace `clk_register(`) with `clk_hw_register()`

The `devm_clk_register()` API is deprecated. Switch to
`devm_clk_hw_register()`.

Since the driver enables its own internal PLLs using the clock API we
still need to get a reference to the PLL clocks using the
`devm_clk_hw_get_clk()` API.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20230326011416.363318-1-lars@metafoo.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>