egl: move dri2_setup_device() after dri2_setup_extensions()

egl: move dri2_setup_device() after dri2_setup_extensions()

dri2_setup_device() will depend on the extensions being set up in
the next commit.

None of the code in-between depends on disp->Device AFAIU.

Signed-off-by: Simon Ser <contact@emersion.fr>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Reviewed-by: Leandro Ribeiro <leandro.ribeiro@collabora.com>
Tested-by: Iago Toral Quiroga <itoral@igalia.com>
Tested-by: Alejandro Piñeiro <apinheiro@igalia.com>
Backport-to: 23.3
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26205>
(cherry picked from commit 9b70096f5e9ab7be23abc9154c3fb83b710ccd6b)