[DO-971] ffmpeg recipe with requirements (!9)

Co-authored-by: aleksandr.vodyanov <aleksandr.vodyanov@avroid.tech>
Reviewed-on: https://git.avroid.tech/Conan/conan_build/pulls/9

recipes/flac/all/test_package/test_package.cpp

@@ -0,0 +1,21 @@
+#include <cstdlib>
+#include <iostream>
+
+#include "FLAC++/encoder.h"
+
+class OurEncoder: public FLAC::Encoder::File {
+public:
+	OurEncoder(): FLAC::Encoder::File() {}
+protected:
+	virtual void progress_callback(FLAC__uint64 bytes_written, FLAC__uint64 samples_written, uint32_t frames_written, uint32_t total_frames_estimate)
+    {}
+};
+
+int main()
+{
+    OurEncoder encoder;
+    if(!encoder) {
+		return EXIT_FAILURE;
+	}
+    return EXIT_SUCCESS;
+}