soc: ti_simplelink: cc13xx-cc26xx: kconfig for subghz 802.15.4

[cfriedt]

Is your enhancement proposal related to a problem? Please describe.
We need to introduce a new Kconfig for IEEE802154_CC13XX_CC26XX_SUB_GHZ in zephyr first, so that we can add the required RF support sources in hal/ti and not receive a check-warns errors like the one below.

Found references to undefined Kconfig symbols. If any of these are false
positives, then add them to UNDEF_KCONFIG_WHITELIST in check_compliance.py in the ci-tools repo.

If the reference is for a comment like /* CONFIG_FOO_* */ (or
/* CONFIG_FOO_*_... */), then please use exactly that form (with the '*'). The
CI check knows not to flag it.

More generally, a reference followed by $, @, {, *, or ## will never be
flagged.

CONFIG_IEEE802154_CC13XX_CC26XX_SUB_GHZ    soc/arm/ti_simplelink/cc13x2_cc26x2/power.c:28
##[error]Process completed with exit code 1.

Describe the solution you'd like
I'll first create a dummy Kconfig entry in soc/arm/ti_simplelink/cc13x2_cc26x2/Kconfig.defconfig.series, defaulting to n, and then we can merge zephyrproject-rtos/hal_ti#22 (may require a DNM PR in Zephyr to show that linking the file in does not break a build).

Describe alternatives you've considered

Additional context
This will be required for the cc1352r to use multiple radio technologies simultaneously, such as the IEEE 802.15.4 2.4 GHz O-QPSK PHY with the IEEE 802.15.4g 915 MHz SUN FSK PHY. Similarly, BLE should be able to run simultaneously with the IEEE 802.15.4g 915 MHz SUN FSK PHY, and BLE can be run concurrently with the IEEE 802.15.4 2.4 GHz O-QPSK PHY using some PHY management on 2.4 GHz.

I have a branch that is nearing completion for #26315 that should be merged after #26316.

[cfriedt]

Fixed by #29598