configs: add defconfig for TS-5x00 SBCs

This patch adds support for the TS-5x00 serie of Technologic Systems
x86-based Single Board Computers, featuring an AMD Elan520 processor.

http://wiki.embeddedarm.com/wiki/#AMD



[Peter: explicitly set arch/variant in defconfig, strip trailing spaces]
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>