package/weston: bump version to 3.0.0

package/weston: bump version to 3.0.0

Added all hashes provided by upstream.

Removed dependency to mtdev after:
https://github.com/wayland-project/weston/commit/167bbb6d109c7c93be3b58232f8c5b8795df44f2

libdrm is now a hard dependency:
https://github.com/wayland-project/weston/commit/b030897b380be4ac8089deecc3db6967dfe7923e

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
[Thomas: drop "select BR2_PACKAGE_LIBDRM" from sub-option, now that it
is selected by the main option.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>