Make sure any errors that occur within the macfb realize chain are detected
and handled correctly to prevent crashes and to ensure that error messages are
reported back to the user.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: BALATON Zoltan <balaton@eik.bme.hu>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20211007221253.29024-2-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>