Don't decompress empty file in stream package

--HG--
branch : feature-streamed-package

code/nel/src/misc/streamed_package_manager.cpp

@@ -231,6 +231,8 @@ bool CStreamedPackageManager::getFile(std::string &filePath, const std::string &
 		// allocate the output buffer :(
 		std::vector<uint8> outBuffer;
 		outBuffer.resize(fileSize);
+		if (fileSize)
+		{
 			// decompress the file in memory
 			ret = LzmaDecode(&state, (unsigned char *)pos, (SizeT)(inBuffer.size() - (pos - &inBuffer[0])), &inProcessed, (unsigned char*)&outBuffer[0], (SizeT)fileSize, &outProcessed);
 			if (ret != 0 || outProcessed != fileSize)
@@ -238,6 +240,7 @@ bool CStreamedPackageManager::getFile(std::string &filePath, const std::string &
 				nlwarning("Failed to decode lzma file '%s'", downloadPath.c_str());
 				return false;
 			}
+		}
 
 		{
 			COFile outStream(unpackPath);