tests: Remove redundant return statements

When the execution reaches the end of the main functions, they implicitly return a successful status.

tests/string/mem.c

@@ -38,5 +38,4 @@ int main(void) {
         return EXIT_FAILURE;
     }
     puts("Correct memcmp");
-    return EXIT_SUCCESS;
 }

tests/string/strcat.c

@@ -1,6 +1,5 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
     char dest1[12] = "hello";
@@ -8,6 +7,4 @@ int main(void) {
 
     char dest2[12] = "hello";
   	printf("%s\n", strncat(dest2, " world foobar", 6)); // should be hello world
-
-    return EXIT_SUCCESS;
 }

tests/string/strchr.c

@@ -1,11 +1,8 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
 	printf("%s\n", strchr("hello", 'e')); // should be ello
 	printf("%s\n", strchr("world", 'l')); // should be ld
 	printf("%i\n", strchr("world", 0) == NULL); // should be 1
-
-    return EXIT_SUCCESS;
 }

tests/string/strcspn.c

@@ -1,11 +1,8 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
 	char *world = "world";
 	printf("%ld\n", strcspn("hello", world)); // should be 2
 	printf("%ld\n", strcspn("banana", world)); // should be 6
-
-    return EXIT_SUCCESS;
 }

tests/string/strncmp.c

@@ -1,6 +1,5 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
     printf("%d\n", strncmp("a", "aa", 2));
@@ -9,6 +8,4 @@ int main(void) {
     printf("%d\n", strncmp("", "\xFF", 1));
     printf("%d\n", strncmp("a", "c", 1));
     printf("%d\n", strncmp("a", "a", 2));
-
-    return EXIT_SUCCESS;
 }

tests/string/strpbrk.c

@@ -1,6 +1,5 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
     char* source = "The quick drawn fix jumps over the lazy bug";
@@ -15,7 +14,5 @@ int main(void) {
 
     // should be "NULL"
     char* res3 = strpbrk(source, "404");
-    printf("%s\n", (res3) ? res3 : "NULL"); 
-
-    return EXIT_SUCCESS;
+    printf("%s\n", (res3) ? res3 : "NULL");
 }

tests/string/strrchr.c

@@ -18,5 +18,4 @@ int main(void) {
     return EXIT_FAILURE;
   }
   printf("strrch PASS, exiting with status code %d\n", 0);
-  return EXIT_SUCCESS;
 }

tests/string/strspn.c

@@ -1,6 +1,5 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
 	char *hello = "hello";
@@ -9,6 +8,4 @@ int main(void) {
 	printf("%lu\n", strspn(hello, "hello")); // should be 5
 	printf("%lu\n", strspn(world, "wendy")); // should be 1
 	printf("%lu\n", strspn(banana, "apple")); // should be 0
-
-    return EXIT_SUCCESS;
 }

tests/string/strstr.c

@@ -1,6 +1,5 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
     printf("%s\n", strstr("In relibc we trust", "rust"));
@@ -8,6 +7,4 @@ int main(void) {
     printf("%s\n", strstr("In relibc we trust", "bugs"));
     printf("%s\n", strstr("IN RELIBC WE TRUST", "rust"));
     printf("%s\n", strcasestr("IN RELIBC WE TRUST", "rust"));
-
-    return EXIT_SUCCESS;
 }

tests/string/strtok.c

@@ -1,6 +1,5 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
     char source[] = "I'd just like to interject for a moment.  What you're referring to as Linux, "
@@ -13,6 +12,4 @@ int main(void) {
             printf("_");
         }
     }
-
-    return EXIT_SUCCESS;
 }

tests/string/strtok_r.c

@@ -1,6 +1,5 @@
 #include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 
 int main(void) {
     char source[] = "I'd just like to interject for a moment.  What you're referring to as Linux, "
@@ -14,6 +13,4 @@ int main(void) {
             printf("_");
         }
     }
-
-    return EXIT_SUCCESS;
 }