cli: Fix assignment for vad_min_silence_duration_ms

[alubbe]

Found and fixed this simple copy/paste error

[danbev]

Thanks! I think we have the same copy & paste error in server.cpp too:

diff --git a/examples/server/server.cpp b/examples/server/server.cpp
index fd9b7784..1262c3d6 100644
--- a/examples/server/server.cpp
+++ b/examples/server/server.cpp
@@ -256,7 +256,7 @@ bool whisper_params_parse(int argc, char ** argv, whisper_params & params, serve
         else if (arg == "-vm"   || arg == "--vad-model")                   { params.vad_model                   = argv[++i]; }
         else if (arg == "-vt"   || arg == "--vad-threshold")               { params.vad_threshold               = std::stof(argv[++i]); }
         else if (arg == "-vspd" || arg == "--vad-min-speech-duration-ms")  { params.vad_min_speech_duration_ms  = std::stoi(argv[++i]); }
-        else if (arg == "-vsd"  || arg == "--vad-min-silence-duration-ms") { params.vad_min_speech_duration_ms  = std::stoi(argv[++i]); }
+        else if (arg == "-vsd"  || arg == "--vad-min-silence-duration-ms") { params.vad_min_silence_duration_ms = std::stoi(argv[++i]); }
         else if (arg == "-vmsd" || arg == "--vad-max-speech-duration-s")   { params.vad_max_speech_duration_s   = std::stof(argv[++i]); }
         else if (arg == "-vp"   || arg == "--vad-speech-pad-ms")           { params.vad_speech_pad_ms           = std::stoi(argv[++i]); }
         else if (arg == "-vo"   || arg == "--vad-samples-overlap")         { params.vad_samples_overlap         = std::stof(argv[++i]); }