Fixed copy and paste error, changed the signature from:

void flushSpy(int c) {}
to:
 void flushSpy(void) {}

test/testdata/testRunnerGenerator.c

@@ -24,7 +24,7 @@
 
 /* Include Passthroughs for Linking Tests */
 void putcharSpy(int c) { (void)putchar(c);}
-void flushSpy(int c) {}
+void flushSpy(void) {}
 
 /* Global Variables Used During These Tests */
 int CounterSetup = 0;