neutrino: clear osd before deleting video and framebuffer

Origin commit data
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Branch: ni/coolstream
Commit: 0ffb8a61e2
Author: vanhofen <vanhofen@gmx.de>
Date: 2021-07-18 (Sun, 18 Jul 2021)

Origin message was:
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- neutrino: clear osd before deleting video and framebuffer

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No further description and justification available within origin commit message!

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This commit was generated by Migit

src/neutrino.cpp

@@ -5746,6 +5746,7 @@ void stop_daemons(bool stopall, bool for_flash)
 
 void stop_video()
 {
+	CFrameBuffer::getInstance()->paintBackground(); // clear osd
 	delete videoDecoder;
 	delete videoDemux;
 	delete CFrameBuffer::getInstance();
@@ -5758,6 +5759,7 @@ void sighandler (int signum)
 	switch (signum) {
 	case SIGTERM:
 	case SIGINT:
+		CVFD::getInstance()->ShowText("Exiting ...");
 #ifdef ENABLE_LCD4LINUX
 		stop_lcd4l_support();
 #endif