x86/paravirt: return full 64-bit result

Impact: Bug fix

A hunk went missing in the original patch, and callee-save callsites were
not marked as returning the upper 32-bit of result, causing Badness.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/include/asm/paravirt.h

@@ -522,7 +522,7 @@ int paravirt_disable_iospace(void);
 					"=c" (__ecx)
 #define PVOP_CALL_CLOBBERS		PVOP_VCALL_CLOBBERS
 
-#define PVOP_VCALLEE_CLOBBERS		"=a" (__eax)
+#define PVOP_VCALLEE_CLOBBERS		"=a" (__eax), "=d" (__edx)
 #define PVOP_CALLEE_CLOBBERS		PVOP_VCALLEE_CLOBBERS
 
 #define EXTRA_CLOBBERS