s390/pci: cleanup clp inline assembly

Tell gcc that the memory region pointed to by req will be used (and
changed). Also remove the (now) superfluous memory constraint.
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/pci/pci_clp.c

@@ -19,18 +19,19 @@
  * Call Logical Processor
  * Retry logic is handled by the caller.
  */
-static inline u8 clp_instr(void *req)
+static inline u8 clp_instr(void *data)
 {
-	u64 ilpm;
+	struct { u8 _[CLP_BLK_SIZE]; } *req = data;
+	u64 ignored;
 	u8 cc;
 
 	asm volatile (
-		"	.insn	rrf,0xb9a00000,%[ilpm],%[req],0x0,0x2\n"
+		"	.insn	rrf,0xb9a00000,%[ign],%[req],0x0,0x2\n"
 		"	ipm	%[cc]\n"
 		"	srl	%[cc],28\n"
-		: [cc] "=d" (cc), [ilpm] "=d" (ilpm)
+		: [cc] "=d" (cc), [ign] "=d" (ignored), "+m" (*req)
 		: [req] "a" (req)
-		: "cc", "memory");
+		: "cc");
 	return cc;
 }