Syscalls have at most 6 argument, not 5. See mmap(2) for example.

Previously the offset argument to mmap(2) would be bogus as we
weren't reading it in.

Approved by: re (kensmith)

usr.bin/truss/main.c

@@ -58,7 +58,7 @@ __FBSDID("$FreeBSD$");
 #include "truss.h"
 #include "extern.h"
 
-#define MAXARGS 5
+#define MAXARGS 6
 
 static void
 usage(void)