KVM: x86 emulator: fix 'and AL,imm8' instruction decoding

'and AL,imm8' should be mask as ByteOp, otherwise the dest operand
length will no correct and we may fill the full EAX when writeback.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/emulate.c

@@ -123,7 +123,7 @@ static u32 opcode_table[256] = {
 	/* 0x20 - 0x27 */
 	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
-	DstAcc | SrcImmByte, DstAcc | SrcImm, 0, 0,
+	ByteOp | DstAcc | SrcImmByte, DstAcc | SrcImm, 0, 0,
 	/* 0x28 - 0x2F */
 	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,