Encoder: add DPMST type
diff --git a/libkms++/encoder.cpp b/libkms++/encoder.cpp
index e3b90fa..34e9c36 100644
--- a/libkms++/encoder.cpp
+++ b/libkms++/encoder.cpp
@@ -27,6 +27,7 @@
 	DEF_ENC(TVDAC),
 	DEF_ENC(VIRTUAL),
 	DEF_ENC(DSI),
+	{ 7, "DPMST" },
 #undef DEF_ENC
 };