V4L/DVB (13941): rj54n1cb0c: remove compiler warning

Remove the following compiler warning: 'dummy' is used uninitialized in this function.
Although the result in the dummy variable is not used the program flow in
soc_camera_limit_side() depends on the value in dummy. The program flow is better
to be deterministic.

Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>