ar71xx: image use the 64kraw template for the TEW-732BR board

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@38140 3c298f89-4303-0410-b956-a3cf2f4a3e73