Externals: Add libLZMA.

Externals/liblzma/common/easy_encoder.c

@@ -0,0 +1,24 @@
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file       easy_encoder.c
+/// \brief      Easy .xz Stream encoder initialization
+//
+//  Author:     Lasse Collin
+//
+//  This file has been put into the public domain.
+//  You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include "easy_preset.h"
+
+
+extern LZMA_API(lzma_ret)
+lzma_easy_encoder(lzma_stream *strm, uint32_t preset, lzma_check check)
+{
+	lzma_options_easy opt_easy;
+	if (lzma_easy_preset(&opt_easy, preset))
+		return LZMA_OPTIONS_ERROR;
+
+	return lzma_stream_encoder(strm, opt_easy.filters, check);
+}