Fixed misc warnings/errors in Solaris build

git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@355 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/pjmedia/include/pjmedia.h b/pjmedia/include/pjmedia.h
index 9a8c423..8cdc0b7 100644
--- a/pjmedia/include/pjmedia.h
+++ b/pjmedia/include/pjmedia.h
@@ -38,6 +38,7 @@
 #include <pjmedia/rtp.h>
 #include <pjmedia/sdp.h>
 #include <pjmedia/sdp_neg.h>
+#include <pjmedia/silencedet.h>
 #include <pjmedia/session.h>
 #include <pjmedia/sound.h>
 #include <pjmedia/sound_port.h>