Update cross build tool links as newer cross build tools
version are provided on Linaro, and attempts to download
the old one give permission denied.
Fixes: 01add9da25cd ("doc: add cross compiling guide")
Cc: stable@dpdk.org
Signed-off-by: Joyce Kong <joyce.kong@arm.com>
Acked-by: Stephen Hemminger <sthemmin@microsoft.com>
Acked-by: Jerin Jacob <jerinj@marvell.com>