runtime: fix arm, arm64, ppc64 builds (I hope)

I guess we need more builders.

Change-Id: I309e3df7608b9eef9339196fdc50dedf5f9422e4
Reviewed-on: https://go-review.googlesource.com/8434Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>

src/runtime/sys_linux_arm.s

@@ -312,7 +312,8 @@ TEXT runtime·clone(SB),NOSPLIT,$0
 // int32 clone0(int32 flags, void *stack, void* fn, void* fnarg);
 TEXT runtime·clone0(SB),NOSPLIT,$0
 	// TODO(spetrovic): Implement this method.
-	MOVW	$-1, ret+16(FP)
+	MOVW	$-1, R0
+	MOVW	R0, ret+16(FP)
 	RET
 
 TEXT runtime·sigaltstack(SB),NOSPLIT,$0

src/runtime/sys_linux_arm64.s

@@ -359,7 +359,8 @@ again:
 // int32 clone0(int32 flags, void *stack, void* fn, void* fnarg);
 TEXT runtime·clone0(SB),NOSPLIT,$0
 	// TODO(spetrovic): Implement this method.
-	MOVW	$-1, ret+32(FP)
+	MOVW	$-1, R0
+	MOVW	R0, ret+32(FP)
 	RET
 
 TEXT runtime·sigaltstack(SB),NOSPLIT,$-8

src/runtime/sys_linux_ppc64x.s

@@ -348,7 +348,8 @@ TEXT runtime·clone(SB),NOSPLIT,$-8
 // int32 clone0(int32 flags, void *stack, void* fn, void* fnarg);
 TEXT runtime·clone0(SB),NOSPLIT,$0
 	// TODO(spetrovic): Implement this method.
-	MOVW	$-1, ret+32(FP)
+	MOVW	$-1, R3
+	MOVW	R3, ret+32(FP)
 	RETURN
 
 TEXT runtime·sigaltstack(SB),NOSPLIT,$-8