buildroot

package/amd-catalyst: Add AMD proprietary graphic stack support

This commits adds support for the AMD Catalyst Linux driver 15.9
(15.201.1151). It includes the fglrx kernel module with various fixes
to make it work with at least Linux kernel 4.4 LTS, the userspace OpenGL
stack and the xorg driver module.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
[Thomas:
 - fixup whitespace issues noticed by Yann.
 - register AMD_CATALYST_PREPARE_MODULE as a post-patch hook rather than
   calling it during the configure step, also suggested by Yann.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>