configure: Fix pseudo-German

configure

@@ -273,7 +273,7 @@ External library support:
   --enable-libzmq          enable message passing via libzmq [no]
   --enable-libzvbi         enable teletext support via libzvbi [no]
   --disable-lzma           disable lzma [autodetect]
-  --enable-decklink        enable Blackmagick DeckLink I/O support [no]
+  --enable-decklink        enable Blackmagic DeckLink I/O support [no]
   --enable-mmal            enable decoding via MMAL [no]
   --enable-nvenc           enable NVIDIA NVENC support [no]
   --enable-openal          enable OpenAL 1.1 capture support [no]