Remove unused variable in tests

Signed-off-by: Mark Harris <mark.hsj@gmail.com>
diff --git a/tests/test_opus_padding.c b/tests/test_opus_padding.c
index c22e8f0..c9ef737 100644
--- a/tests/test_opus_padding.c
+++ b/tests/test_opus_padding.c
@@ -39,7 +39,7 @@
 #define CHANNELS 2
 #define FRAMESIZE 5760
 
-int test_overflow(void)
+void test_overflow(void)
 {
   OpusDecoder *decoder;
   int result;
@@ -51,7 +51,7 @@
   fprintf(stderr, "  Checking for padding overflow... ");
   if (!in || !out) {
     fprintf(stderr, "FAIL (out of memory)\n");
-    return -1;
+    test_failed();
   }
   in[0] = 0xff;
   in[1] = 0x41;
@@ -71,21 +71,18 @@
   }
 
   fprintf(stderr, "OK.\n");
-
-  return 1;
 }
 
 int main(void)
 {
   const char *oversion;
-  int tests = 0;;
 
   iseed = 0;
   oversion = opus_get_version_string();
   if (!oversion) test_failed();
   fprintf(stderr, "Testing %s padding.\n", oversion);
 
-  tests += test_overflow();
+  test_overflow();
 
   fprintf(stderr, "All padding tests passed.\n");