DeadCode: use stdbool for dead code test case

Author: lcartey

c/common/test/rules/deadcode/DeadCode.expected

@@ -1,11 +1,11 @@
-| test.c:20:3:20:27 | declaration | This statement is dead code. |
-| test.c:21:3:21:12 | ExprStmt | This statement is dead code. |
-| test.c:22:3:22:12 | ExprStmt | This statement is dead code. |
-| test.c:24:3:26:3 | if (...) ...  | This statement is dead code. |
-| test.c:36:3:37:3 | if (...) ...  | This statement is dead code. |
-| test.c:39:3:39:4 | { ... } | This statement is dead code. |
-| test.c:40:3:42:3 | { ... } | This statement is dead code. |
-| test.c:56:6:57:3 | { ... } | This statement is dead code. |
-| test.c:67:46:68:3 | { ... } | This statement is dead code. |
-| test.c:71:3:71:8 | ExprStmt | This statement is dead code. |
-| test.c:73:3:73:21 | ExprStmt | This statement is dead code. |
+| test.c:18:3:18:27 | declaration | This statement is dead code. |
+| test.c:19:3:19:12 | ExprStmt | This statement is dead code. |
+| test.c:20:3:20:12 | ExprStmt | This statement is dead code. |
+| test.c:22:3:24:3 | if (...) ...  | This statement is dead code. |
+| test.c:34:3:35:3 | if (...) ...  | This statement is dead code. |
+| test.c:37:3:37:4 | { ... } | This statement is dead code. |
+| test.c:38:3:40:3 | { ... } | This statement is dead code. |
+| test.c:54:6:55:3 | { ... } | This statement is dead code. |
+| test.c:65:46:66:3 | { ... } | This statement is dead code. |
+| test.c:69:3:69:8 | ExprStmt | This statement is dead code. |
+| test.c:71:3:71:21 | ExprStmt | This statement is dead code. |

c/common/test/rules/deadcode/test.c

@@ -1,8 +1,6 @@
 // NOTICE: THE TEST CASES BELOW ARE ALSO INCLUDED IN THE C++ TEST CASE AND
 // CHANGES SHOULD BE REFLECTED THERE AS WELL.
-// Define true/false for compatibility with C++ test cases
-#define false 0
-#define true 1
+#include<stdbool.h>
 
 int may_have_side_effects();
 int no_side_effects(int x) { return 1 + 2; }