MIPS: Loongson: Fix find_vga_mem_init()

This allows to use all display device for instance DISPLAY_OTHER like SM501.

Signed-off-by: Arnaud Patard <apatard@mandriva.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1160/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>