Based on the HAL from stm32wl, the peripheral driver has been
modified to fit into embassy, using the embassy APIs, providing
operation of the radio peripheral.
The initial version does not offer any async APIs, but the example
shows how the radio IRQ can be used to perform async TX of the radio.
Currently this looks up the frequency in the global singleton that must
be initialized by the per-chip RCC implementation. At present, this is
only done for the L0 family of chips.
Adds RccPeripheral trait for peripherals implementing clock enable and reset for a given peripheral.
Add macro table generting implementations of RccPeripheral for peripherals with clock set, currently restricted to SPI.
* SPI write v2 was hanging in write due to an infinite loop
* SPI word write was not followed by a read back
The u8 and u16 write/read logic have been refactored into write_word and
read_word.
