[babl] make fish hashes less likely to fail

[Øyvind Kolås <ok src gnome org>]

commit 4c8edae7cb5fbbfedc5dd9884d94b0495dfc5702
Author: Øyvind Kolås <pippin gimp org>
Date:   Sat Dec 31 20:26:35 2016 +0100

    make fish hashes less likely to fail

 babl/babl-fish.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/babl/babl-fish.c b/babl/babl-fish.c
index 76cb53d..96c69c3 100644
--- a/babl/babl-fish.c
+++ b/babl/babl-fish.c
@@ -133,6 +133,8 @@ babl_fish_get_id (const Babl *source,
    * source/destination values. */
   ptrdiff_t id = source - destination;
   /* instances with id 0 won't be inserted into database */
+  id *= ((((size_t)  (source))) % 37);
+
   if (id == 0)
     id = 1;
   return id;