Improved HFCLK management on nRF5x

[Matt-prog]

Related area

device controller driver

Hardware specification

nRF5x

Is your feature request related to a problem?

When SoftDevice is not present or is disabled, HFCLK activation/deactivation is managed by TinyUSB. This can cause problems, when other peripherials, such as Radio, needs HFCLK to run properly.

Describe the solution you'd like

I have improved HFCLK management for nRF5x with weak functions, the user can override and implement it's own HFCLK management, when other peripherials, such as Radio needs it.

User can override those functions:
void dcd_enable_hfclk(void); - called, when dcd requests HFCLK activation
void dcd_disable_hfclk(void); - called, when dcd requests HFCLK deactivation

If the functions are not overridden, HFCLK will be activated and deactivated by TinyUSB.

I have implemented this feature, see Pull Request.

I have checked existing issues, dicussion and documentation

• I confirm I have checked existing issues, dicussion and documentation.