kinetis: move filtering-out periph_hwrng in cpu/kinetis

[cladmi]

Contribution description

This removes doing filter-out periph_hwrng, $(FEATURES_PROVIDED)
after processing cpu/$(CPU)/Makefile.features.
The current solution is a HACK as CPU_MODEL is currently not available
at that moment but will be in the near future.

It will allow always including cpu/$(CPU)/Makefile.features after
boards/$(BOARD)/Makefile.features.

It is a part of moving CPU/CPU_MODEL definitions to Makefile.features.

Testing procedure

For all the modified boards, the provided features are the same as in master.
I only checked examples/hello-world as it should not change anything for these ones.

for board in frdm-k64f frdm-kw41z phynode-kw41z teensy31 usb-kw41z; do echo ${board}; BOARD=${board} make --no-print-directory -C examples/hello-world info-debug-variable-FEATURES_PROVIDED; done
frdm-k64f
periph_adc periph_i2c periph_pwm periph_rtc periph_rtt periph_spi periph_timer periph_uart periph_cpuid periph_gpio periph_gpio_irq periph_mcg periph_pm cpp
frdm-kw41z
periph_adc periph_i2c periph_rtc periph_rtt periph_spi periph_timer periph_uart periph_cpuid periph_gpio periph_gpio_irq periph_mcg periph_pm cpp
phynode-kw41z
periph_adc periph_i2c periph_rtc periph_rtt periph_spi periph_timer periph_uart periph_cpuid periph_gpio periph_gpio_irq periph_mcg periph_pm cpp
teensy31
periph_pwm periph_rtc periph_rtt periph_timer periph_uart periph_cpuid periph_gpio periph_gpio_irq periph_mcg periph_pm cpp
usb-kw41z
periph_adc periph_i2c periph_rtc periph_rtt periph_spi periph_timer periph_uart periph_cpuid periph_gpio periph_gpio_irq periph_mcg periph_pm cpp

I also looked at all boards to verify they did not change but did not post the output.

Issues/PRs references

Required to apply #11478
Split out of #11477

[aabadie]

ACK for the proposed HACK. I would just reword a bit the comments.

[aabadie]

This comment has too much personal taste (e.g. don't use I prefer). Maybe reword with: A whitelist on CPU_MODEL would be better but this information/variable is not available yet.

[cladmi]

Indeed, will change.

[aabadie]

If I understand this correctly, the wrong hwrng register is used for frdm-k64f ? Maybe make this more explicit that this HACK applies to frdm-kw64f.

[cladmi]

I forgot to re-precise this when moving it to the common directory.

[cladmi]

While re-reading I am not sure if it is the frdm-k64f or the CPU_MODEL completely. That is why I wrote board/cpu_model. I think it may be more cpu_model but hard to know without debugging why.

I can change to Hack, either the board or the cpu_model currently uses the wrong hwrng maybe ?

[aabadie]

Maybe start the next sentence on the same line:
HACK the board/cpu_model currently uses the wrong hwrng register. Remove next line when fixed (you can split it if it's too long)

[cladmi]

I can just remove the "remove next line when fixed" as it is implicit and still precise the frdm as it is currently the only one I know as you said in the first comment.
The HWRNG uses the wrong hwrng register for the frdm-k64f board/cpu_model

[aabadie]

Looks good now. ACK

Please squash

[cladmi]

Squashed.

[aabadie]

and go!

[cladmi]

Thanks :)