thermal: int340x: Consolidate freeing of acpi_buffer pointer

Introduce a single point of freeing/exit after ensuring no error in
int3400_setup_gddv().

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>