KVM: x86/emulator: emulate movbe with operand-size prefix

The MOVBE instruction can come with an operand-size prefix (66h). In
this, case the x86 emulation code returns EMULATION_FAILED.

It turns out that em_movbe can already handle this case and all that
is missing is an entry in respective opcode tables to populate
gprefix->pfx_66.

Signed-off-by: Thomas Prescher <[email protected]>
Signed-off-by: Julian Stecklina <[email protected]>
Acked-by: Borislav Petkov (AMD) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sean Christopherson <[email protected]>

Author: tpressure

arch/x86/kvm/emulate.c

@@ -4505,11 +4505,11 @@ static const struct instr_dual instr_dual_0f_38_f1 = {
 };
 
 static const struct gprefix three_byte_0f_38_f0 = {
-	ID(0, &instr_dual_0f_38_f0), N, N, N
+	ID(0, &instr_dual_0f_38_f0), ID(0, &instr_dual_0f_38_f0), N, N
 };
 
 static const struct gprefix three_byte_0f_38_f1 = {
-	ID(0, &instr_dual_0f_38_f1), N, N, N
+	ID(0, &instr_dual_0f_38_f1), ID(0, &instr_dual_0f_38_f1), N, N
 };
 
 /*