boards: xtensa: intel_adsp_cavs25: Rename board with HWMv2

Rename for better HWMv2 use:
 board - `intel_adsp_cavs25` to `intel_adsp`

Resulting name changes for boards:
 `intel_adsp_cavs25/cavs25`      -> `intel_adsp/cavs25`
 `intel_adsp_cavs25/cavs25/tgph` -> `intel_adsp/cavs25/tgph`

Signed-off-by: Dmitrii Golovanov <dmitrii.golovanov@intel.com>