Shared memory mappings on nommu machines require a get_unmapped_area
file operation that suggests an address for the mapping. This patch
adds a way for v4l2 drivers to provide this callback.
Signed-off-by: NDaniel Glöckner <dg@emlix.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>