libcamera: framebuffer: Replace vector with span in constructor

The FrameBuffer constructor takes a list of planes as an std::vector.
The caller may stores the planes in a different type of container,
resulting in the needless allocation of a temporary vector. Replace it
with a span.

Suggested-by: Daniel Rákos <daniel.rakos@rastergrid.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>

src/libcamera/pipeline/rpi/common/pipeline_base.cpp

@@ -883,8 +883,10 @@ void PipelineHandlerBase::mapBuffers(Camera *camera, const BufferMap &buffers, u
 	 * handler and the IPA.
 	 */
 	for (auto const &[id, buffer] : buffers) {
-		bufferIds.push_back(IPABuffer(mask | id,
-					      buffer.buffer->planes()));
+		Span<const FrameBuffer::Plane> planes = buffer.buffer->planes();
+
+		bufferIds.emplace_back(mask | id,
+				       std::vector<FrameBuffer::Plane>{ planes.begin(), planes.end() });
 		data->bufferIds_.insert(mask | id);
 	}