linux-dmabuf: advertise format modifiers with modifier event

advertise the supported fourcc format modifiers along with supported
formats to the client. the 'modifier' event introduced here is
intended to replace the 'format' event from zwp_linux_dmabuf_v1
version 1.

bump zwp_linux_dmabuf_v1, zwp_linux_buffer_params_v1 interface
versions to 3.

v2: specify request name in event description for clarity (Yong Bakos)
v3: grammar fixup (Yong Bakos)
v4: add deprecation warning against 'format' event usage (pq)

Signed-off-by: Varad Gautam <varad.gautam@collabora.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-by: Yong Bakos <ybakos@humanoriented.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>