Pre-release version bump to 0.33.6

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
diff --git a/configure.ac b/configure.ac
index ae4d3c6..3ada8e6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -54,7 +54,7 @@
 
 m4_define([pixman_major], 0)
 m4_define([pixman_minor], 33)
-m4_define([pixman_micro], 5)
+m4_define([pixman_micro], 6)
 
 m4_define([pixman_version],[pixman_major.pixman_minor.pixman_micro])