Debian: Build with enabled SMPP support

Change-Id: Ibab5ede36cf329620a66b7811c43cc73c7135ecd
diff --git a/debian/control b/debian/control
index f6ea826..722a1bc 100644
--- a/debian/control
+++ b/debian/control
@@ -12,6 +12,7 @@
                libdbi-dev,
                libtalloc-dev,
                libssl-dev,
+               libsmpp34-dev,
                libasn1c-dev,
                libosmocore-dev,
                libosmo-sccp-dev,