build: bump libbson.

Christian Hergert · Christian Hergert · commit f12e41781c4c · 2014-06-18T23:43:43.000-07:00
diff --git a/src/libbson b/src/libbson
@@ -1 +1 @@
-Subproject commit af039f005c509b04f47dde05e0d545e810213159
+Subproject commit 1fdcfb04aa15940ca4c703062ac5f3708a500b0c
