Fix parser bug with ranges

The change to allow -/+ for values broke ranges.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/parse.h b/parse.h
index f2265a4..f1f3927 100644
--- a/parse.h
+++ b/parse.h
@@ -75,7 +75,7 @@
 
 extern void strip_blank_front(char **);
 extern void strip_blank_end(char *);
-extern int str_to_decimal(const char *, long long *, int, void *);
+extern int str_to_decimal(const char *, long long *, int, int, void *);
 
 /*
  * Handlers for the options