media: camss: vfe-4-7: Rename get_ub_size, set_qos, set_ds, wm_enable

In preparation to add support for VFE 4.8, rename these functions
by adding the vfe version that they are referred to (for example,
vfe_get_ub_size -> vfe47_get_ub_size), as these are the only ones
that will be different for the VFE version 4.8.

Signed-off-by: AngeloGioacchino Del Regno <kholk11@gmail.com>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>