Fix FE_FETCH_R_SIMPLE specialization

After a99d08b the type can
include UNDEF. However, UNDEF can only reach FE_FREE, not FE_FETCH.
As such, simply ignore this type.

Author: nikic

Zend/zend_vm_def.h

@@ -9571,7 +9571,7 @@ ZEND_VM_HOT_TYPE_SPEC_HANDLER(ZEND_SEND_VAL_EX, op->op2_type == IS_UNUSED && op-
 	ZEND_VM_NEXT_OPCODE();
 }
 
-ZEND_VM_HOT_TYPE_SPEC_HANDLER(ZEND_FE_FETCH_R, op->op2_type == IS_CV && (op1_info & (MAY_BE_UNDEF|MAY_BE_ANY|MAY_BE_REF)) == MAY_BE_ARRAY, ZEND_FE_FETCH_R_SIMPLE, VAR, CV, JMP_ADDR, SPEC(RETVAL))
+ZEND_VM_HOT_TYPE_SPEC_HANDLER(ZEND_FE_FETCH_R, op->op2_type == IS_CV && (op1_info & (MAY_BE_ANY|MAY_BE_REF)) == MAY_BE_ARRAY, ZEND_FE_FETCH_R_SIMPLE, VAR, CV, JMP_ADDR, SPEC(RETVAL))
 {
 	USE_OPLINE
 	zval *array;

Zend/zend_vm_execute.h

@@ -61967,7 +61967,7 @@ ZEND_API void ZEND_FASTCALL zend_vm_set_opcode_handler_ex(zend_op* op, uint32_t
 			}
 			break;
 		case ZEND_FE_FETCH_R:
-			if (op->op2_type == IS_CV && (op1_info & (MAY_BE_UNDEF|MAY_BE_ANY|MAY_BE_REF)) == MAY_BE_ARRAY) {
+			if (op->op2_type == IS_CV && (op1_info & (MAY_BE_ANY|MAY_BE_REF)) == MAY_BE_ARRAY) {
 				spec = 3421 | SPEC_RULE_RETVAL;
 			}
 			break;