media: via-camera: deleted these redundant semicolons

Macros should not use a trailing semicolon，and it was used
the semicolon after macro cam_dbg called in viacam_vb2_prepare,
so deleted these redundant semicolons.

Signed-off-by: lijian <lijian@yulong.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>