s390/sthyi: use register pair instead of register asm

static int sthyi(u64 vaddr, u64 *rc)

{

	register u64 code asm("0") = 0;

	register u64 addr asm("2") = vaddr;

	register u64 rcode asm("3");

	union register_pair r1 = { .even = 0, }; /* subcode */

	union register_pair r2 = { .even = vaddr, };

	int cc;

	asm volatile(

		".insn   rre,0xB2560000,%[code],%[addr]\n"

		".insn   rre,0xB2560000,%[r1],%[r2]\n"

		"ipm     %[cc]\n"

		"srl     %[cc],28\n"

		: [cc] "=d" (cc), "=d" (rcode)

		: [code] "d" (code), [addr] "a" (addr)

		: [cc] "=&d" (cc), [r2] "+&d" (r2.pair)

		: [r1] "d" (r1.pair)

		: "memory", "cc");

	*rc = rcode;

	*rc = r2.odd;

	return cc;

}