Originally the upper value for image size and extra size is 1024M, which
is relatively small. Enlarge it to 64GB.
Besides, fix tooltip for toolchain build.
(Bitbake rev: 99f01305b4c2253567a1a13a33339b1755a86e6d)
Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>