patch 9.1.0588: The maze program no longer compiles on newer clang

Problem:  The maze program no longer compiles on newer clang
Solution: Use ANSI C function definition for main()
          (Mohamed Akram)

Implicit int is an error in newer versions of clang.

closes: #15247

Signed-off-by: Mohamed Akram <mohd.akram@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/macros/maze/mazeclean.c

@@ -8,7 +8,7 @@
 
 char *M, A, Z, E = 40, line[80], T[3];
 int
-main (C)
+main (int C)
 {
   for (M = line + E, *line = A = scanf ("%d", &C); --E; line[E] = M[E] = E)
     printf ("._");

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    588,
 /**/
     587,
 /**/