[Liftoff][mips] Fix cctest/test-run-wasm/RunWasmLiftoff_ExprBlock_ManualSwitch_brif

Test started failing after commit `[Liftoff] Remove Get{Unary,Binary}OpTargetRegister`.
Optimization shouldn't be done if dst == rhs in i32_set_cond instruction.
This CL fixes the issue.

Change-Id: I67cd1ca4692fcf69202ef25f7aa58756a5ddddca
Reviewed-on: https://chromium-review.googlesource.com/952963Reviewed-by: Ivica Bogosavljevic <ivica.bogosavljevic@mips.com>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Ivica Bogosavljevic <ivica.bogosavljevic@mips.com>
Cr-Commit-Position: refs/heads/master@{#51806}

src/wasm/baseline/mips/liftoff-assembler-mips.h

@@ -431,7 +431,7 @@ void LiftoffAssembler::emit_cond_jump(Condition cond, Label* label,
 void LiftoffAssembler::emit_i32_set_cond(Condition cond, Register dst,
                                          Register lhs, Register rhs) {
   Label true_label;
-  if (dst != lhs) {
+  if (dst != lhs && dst != rhs) {
     ori(dst, zero_reg, 0x1);
   }
 
@@ -443,7 +443,7 @@ void LiftoffAssembler::emit_i32_set_cond(Condition cond, Register dst,
   // If not true, set on 0.
   TurboAssembler::mov(dst, zero_reg);
 
-  if (dst != lhs) {
+  if (dst != lhs && dst != rhs) {
     bind(&true_label);
   } else {
     Label end_label;

src/wasm/baseline/mips64/liftoff-assembler-mips64.h

@@ -376,7 +376,7 @@ void LiftoffAssembler::emit_cond_jump(Condition cond, Label* label,
 void LiftoffAssembler::emit_i32_set_cond(Condition cond, Register dst,
                                          Register lhs, Register rhs) {
   Label true_label;
-  if (dst != lhs) {
+  if (dst != lhs && dst != rhs) {
     ori(dst, zero_reg, 0x1);
   }
 
@@ -388,7 +388,7 @@ void LiftoffAssembler::emit_i32_set_cond(Condition cond, Register dst,
   // If not true, set on 0.
   TurboAssembler::mov(dst, zero_reg);
 
-  if (dst != lhs) {
+  if (dst != lhs && dst != rhs) {
     bind(&true_label);
   } else {
     Label end_label;