toolchain-external: update Linaro AArch64 toolchains

Add Linaro AArch64 2013.10 and Linaro AArch64 2013.11, and remove
Linaro AArch64 2013.07 and Linaro AArch64 2013.08.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>