Fixed a few compiler warnings

git-svn-id: svn://svn.cc65.org/cc65/trunk@935 b7a2c559-68d2-44c3-8de9-860c34a00d81

src/ar65/main.c

@@ -77,7 +77,7 @@ static void Usage (void)
 int main (int argc, char* argv [])
 /* Assembler main program */
 {
-    int I;
+    unsigned I;
 
     /* Initialize the cmdline module */
     InitCmdLine (&argc, &argv, "ar65");