debian: Fix dependencies pointed out by lintian

E: openbsc source: missing-separator-between-items in osmocom-nitb depends field between '${misc:Depends}' and 'libdbd-sqlite3'
diff --git a/debian/control b/debian/control
index 32c75db..ad0cc89 100644
--- a/debian/control
+++ b/debian/control
@@ -16,7 +16,7 @@
 
 Package: osmocom-nitb
 Architecture: any
-Depends: ${shlibs:Depends}, ${misc:Depends} libdbd-sqlite3
+Depends: ${shlibs:Depends}, ${misc:Depends}, libdbd-sqlite3
 Description: GSM Network-in-a-Box, implements BSC, MSC, SMSC, HLR, VLR
  All the GSM network components bundled together.