libcamera: fix compilation error
Upstream libcamera commit 32635054bc76e2ababd8ea2177fca1f88229541a changed "planes" on FrameMetadata
to be a function. Adapt the plugin code accordingly.
Upstream libcamera commit 32635054bc76e2ababd8ea2177fca1f88229541a changed "planes" on FrameMetadata
to be a function. Adapt the plugin code accordingly.