Use the KERNEL_SUFFIX variable in Build/sdcard-img, rather than
using hardcoded "-kernel.bin", to allow overriding KERNEL_SUFFIX for a
device.
Fixes: 080a769b4d ("qoriq: new target")
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
(cherry picked from commit 86948716db)