We need to convert svg into png in the docs build so add rsvg tools
to handle this.
(From OE-Core rev: 5dd1fdf4c3e8596c4e7c8cd57d371c2c1d4b0843)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>