egl: automake: include builddir prior to srcdir

Analogous to previous commit.

Cc: "12.0 13.0" <mesa-dev@lists.freedesktop.org>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
(cherry picked from commit c5921ae0d2fc37699c7ebbd693a2e850a5371204)
1 file changed