Fix unused parameter compiler warnings in check tools

testsuite/sanei/sanei_usb_test.c

@@ -827,7 +827,7 @@ test_attach (void)
 }
 
 int
-main (int argc, char **argv)
+main (int __sane_unused__ argc, char **argv)
 {
   int detected, opened, i;
   SANE_Int dn[MAX_DEVICES];

testsuite/sanei/test_wire.c

@@ -54,7 +54,7 @@ Valid CODECs are: `ascii' `bin'\n", program_name, default_codec, default_outfile
 
 
 int
-main (int argc, char **argv)
+main (int __sane_unused__ arg, char **argv)
 {
   SANE_Option_Descriptor desc[2], *desc_ptr;
   SANE_Word len;