intel_adsp: Move power domains under lps node for now
intel_adsp: Move power domains under lps node for now

As the power domain nodes don't represent something accessible via
a MMIO register move those under the lps node to address warnings
generated when building the DTS.

Signed-off-by: Kumar Gala <a5e5248af4cd4f0ed8c515f61d40a6e2db46a66e@intel.com>

zephyrproject-rtos/zephyr,galak/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,galak/zephyr