xcmsdb: Add libxdmcp to DEPENDS

Signed-off-by: Joshua Lock <josh@linux.intel.com>

meta-moblin/packages/xorg-app/xcmsdb_1.0.1.bb

@@ -1,4 +1,4 @@
 require xorg-app-common.inc
 PE = "1"
 
-DEPENDS += " virtual/libx11"
+DEPENDS += " virtual/libx11 libxdmcp"