Bump apu_version.h for 0.9.1 release


git-svn-id: https://svn.apache.org/repos/asf/apr/apr-util/trunk@58747 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/include/apu_version.h b/include/apu_version.h
index 1620780..587c318 100644
--- a/include/apu_version.h
+++ b/include/apu_version.h
@@ -108,7 +108,7 @@
  *  This symbol is defined for internal, "development" copies of APU. This
  *  symbol will be #undef'd for releases. 
  */
-#define APU_IS_DEV_VERSION
+#undef APU_IS_DEV_VERSION
 
 /** The formatted string of APU's version */
 #define APU_VERSION_STRING \