libcamera: request: Rename Private::reuse() to Private::reset()

The Request::Private::reuse() is different from Request::reuse().
It resets the members of Request::Private to default values hence,
rename it to a more appropriate Request::Private::reset().

Update the usage and documentation accordingly.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

include/libcamera/internal/request.h

@@ -37,7 +37,7 @@ public:
 	bool completeBuffer(FrameBuffer *buffer);
 	void complete();
 	void cancel();
-	void reuse();
+	void reset();
 
 	void prepare(std::chrono::milliseconds timeout = 0ms);
 	Signal<> prepared;