Remove extra mul op

src/rewrite_gelu.cpp

@@ -51,8 +51,7 @@ struct find_gelu_erf
         one      = m.insert_instruction(
             ins, make_op("multibroadcast", {{"out_lens", x->get_shape().lens()}}), one);
         sig = m.insert_instruction(ins, make_op("add"), sig, one);
-        sig = m.insert_instruction(ins, make_op("div"), one, sig);
-        sig = m.insert_instruction(ins, make_op("mul"), x, sig);
+        sig = m.insert_instruction(ins, make_op("div"), x, sig);
         m.replace_instruction(ins, sig);
     }
 };

test/rewrite_gelu_test.cpp

@@ -77,8 +77,7 @@ TEST_CASE(bias_gelu)
         auto l2  = m2.add_literal(migraphx::literal{s2, {1.0f}});
         l2 = m2.add_instruction(migraphx::make_op("multibroadcast", {{"out_lens", s1.lens()}}), l2);
         sig = m2.add_instruction(migraphx::make_op("add"), sig, l2);
-        sig = m2.add_instruction(migraphx::make_op("div"), l2, sig);
-        sig = m2.add_instruction(migraphx::make_op("mul"), add, sig);
+        sig = m2.add_instruction(migraphx::make_op("div"), add, sig);
         m2.add_return({sig});
     }
 
@@ -125,8 +124,7 @@ TEST_CASE(non_bias_gelu)
         auto l2  = m2.add_literal(migraphx::literal{s2, {1.0f}});
         l2 = m2.add_instruction(migraphx::make_op("multibroadcast", {{"out_lens", s1.lens()}}), l2);
         sig = m2.add_instruction(migraphx::make_op("add"), sig, l2);
-        sig = m2.add_instruction(migraphx::make_op("div"), l2, sig);
-        sig = m2.add_instruction(migraphx::make_op("mul"), sub, sig);
+        sig = m2.add_instruction(migraphx::make_op("div"), sub, sig);
         m2.add_return({sig});
     }