cc2650_sensortag_defconfig assigned missing Kconfig symbols (now dead code)

[ulfalizer]

The following Kconfig symbols never existed, but are assigned in boards/arm/cc2650_sensortag/cc2650_sensortag_defconfig:

• PINMUX_CC2650_INIT_PRIO
• CC2650_TRNG_IRQ_PRIO
• CC2650_TRNG_ENTROPY_GENERATOR

Only the last one is referenced elsewhere, giving some dead code:

arch/arm/soc/ti_simplelink/cc2650/soc.c:#ifdef CONFIG_CC2650_TRNG_ENTROPY_GENERATOR
arch/arm/soc/ti_simplelink/cc2650/soc.c:	defined(CONFIG_CC2650_TRNG_ENTROPY_GENERATOR) || \
arch/arm/soc/ti_simplelink/cc2650/soc.c:#if defined(CONFIG_GPIO_CC2650) || defined(CONFIG_CC2650_TRNG_ENTROPY_GENERATOR)
arch/arm/soc/ti_simplelink/cc2650/soc.c:#ifdef CONFIG_CC2650_TRNG_ENTROPY_GENERATOR
arch/arm/soc/ti_simplelink/cc2650/soc.c:#if defined(CONFIG_GPIO_CC2650) || defined(CONFIG_CC2650_TRNG_ENTROPY_GENERATOR)

The #ifdefs were renamed by commit da9b0dd (drivers: Rename random to entropy), but no symbol with the old name exists either.

[ulfalizer]

CC @ClumsyApe @nashif

Trying to get rid of assignments to undefined Kconfig symbols, to turn it into an error.

[GAnthony]

I could remove what appears to be the dead code, but I don't have this board to test.

@ClumsyApe, I see cc2650_sensortag doesn't build for the blinky sample, and wonder if this board is even being used. Can you please comment on the intention of the TRNG support?

[ulfalizer]

I submitted a PR that just removes the Kconfig assignments: #7929. Trying to get of all assignments to undefined symbols to turn it into an error.

Remove the dead code too if it isn't used.