CLWB isn't supported on Ice Lake client.  But Ice Lake server and Tiger
Lake support it.  Move PTA_CLWB to PTA_ICELAKE_SERVER and PTA_TIGERLAKE.

	PR target/95874
	* config/i386/i386.h (PTA_ICELAKE_CLIENT): Remove PTA_CLWB.
	(PTA_ICELAKE_SERVER): Add PTA_CLWB.
	(PTA_TIGERLAKE): Add PTA_CLWB.

(cherry picked from commit c422e5f81f42a0fc197f0715f4fcd81f1be90bff)