* Refactor GRTC peripheral splitting it into multiple channels
* Reserve channel 1 for time-driver if enabled
* Implement time-driver using GRTC (RTC peripheral is now removed).
* Add timer example to nrf54l15

Both SVD and documentation agrees on 1524kB

embassy-nrf: add `gpiote::InputChannel::wait_for_high/low()`

The CRACEN peripheral supports random number generation,
digest and key generation, and key exchange.

The initial support implements random number generation.

Also catch GPIOTE events directly when wait() is called, even before
polling the future.