soc: intel_adsp: DCACHE_LINE_SIZE was not defined

The symbol DCACHE_LINE_SIZE was not being defined in Intel ADSP
targets.

It fixes the following problem:

/zephyr/soc/intel/intel_adsp/ace/power.c:30:29: error:
'CONFIG_DCACHE_LINE_SIZE' undeclared here (not in a function); did you
mean 'XCHAL_DCACHE_LINESIZE'?  30 | uint8_t
adsp_pending_buffer[CONFIG_DCACHE_LINE_SIZE]
__aligned(CONFIG_DCACHE_LINE_SIZE);

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>