fix: add a blank implement for the linux platform

components/vision/port/linux/maix_uvc_stream.cpp

@@ -0,0 +1,44 @@
+#include <bits/stdc++.h>
+#include <functional>
+
+#include <termios.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+
+#include "maix_uvc_stream.hpp"
+
+extern "C" {
+
+extern int uvc_main_exist;
+extern int uvc_main(int argc, char *argv[]);
+
+int uvc_video_fill_mjpg_buffer(void *buf, uint32_t *size) {
+    return -1;
+}
+
+}
+
+namespace maix::uvc
+{
+int helper_fill_mjpg_image(void* buf, uint32_t* size, image::Image *img) {
+    return -1;
+}
+
+// 静态成员定义
+UvcServer *UvcServer::_instance = nullptr;
+
+void UvcServer::run() { }
+
+void UvcServer::stop() { }
+
+UvcStreamer::UvcStreamer(): _using_jpeg(0) { }
+
+UvcStreamer::~UvcStreamer() { }
+
+
+err::Err UvcStreamer::show(image::Image *img) {
+    return err::ERR_NOT_IMPL;
+}
+
+}