s390: Corrections to brxh / brxhg cctests in test-assembler-s390.cc

Change-Id: I991686d6890909510d2a3e7101230995ff521063
Reviewed-on: https://chromium-review.googlesource.com/1152081Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#54792}

test/cctest/test-assembler-s390.cc

@@ -574,20 +574,6 @@ TEST(12) {
   __ brxhg(r1, r3, &continue2);
   __ b(&failed);
 
-  __ lgfi(r1, Operand(1));
-  __ lgfi(r3, Operand(1));
-  __ brxhg(r1, r3, &continue1);
-  __ b(&failed);
-
-  __ bind(&continue1);
-  __ lgfi(r1, Operand(-2));
-  __ lgfi(r3, Operand(1));
-  __ brxhg(r1, r3, &failed);
-  __ brxhg(r1, r3, &failed);
-  __ brxhg(r1, r3, &failed);
-  __ brxhg(r1, r3, &continue2);
-  __ b(&failed);
-
   //r1 - operand; r4 - inc; r5 - test val
   __ bind(&continue2);
   __ lgfi(r1, Operand(-2));