libcamera: fix code indentation
libcamera: show FPS
libcamera: lower preview framerate
libcamera: reorganize code
libcamera: grab frame only once while recording

This change almost doubles the fps
libcamera: customizable preview framerate
libcamera: use grabPreviewFrame while recording
etc: update media_profiles.xml
libcamera: adjust number of frames to skip
libcamera: fix compiler warnings
libcamera: wait for the release of the buffers
libcamera: request memory as soon as the preview starts
libcamera: count with stride
libcamera: store the resized frame in a different memory location

This prevents unresized and unrotated frames from being shown when
the front facing camera is used.
libcamera: request and release memory once
Revert "libcamera: request and release memory once"

It makes some third party apps crash.

This reverts commit fd547097ddebbba38e0a33884031441cce0fb914.
libcamera: colour conversion optimization

Adapted from Defy, thanks to nadlabak.
libcamera: changes to setPreviewWindow

Adapted from Crespo
libcamera: don't drop initial frames

It's not preventing garbled frames anyway.
libcamera: skip less preview frames while recording

We now use a lighter colour conversion.