libcamera is depending on libdrm in libcamera_wrapper.cpp but it was
implicitely including the header drm_fourcc.h with libcamera
file pixel_format.h
With this patch, the libcamera plugin should explicitely depends on
libdrm as it needs DRM fourcc and should not depend on multiple
inclusion from libcamera.
Add a FourCC for Motion-JPEG compressed format. This is a temporary
addition until the format gets merged in the upstream kernel.