Revert "Hammerhead: change linaro version to 4.8"

This reverts commit f6920bcbb2e125396e5ea2096c7300edcf10e64f.

Change-Id: Idd95cfe6bc9cc1590e53aefb01745f447b3791b4
Merge "Revert "Hammerhead: change linaro version to 4.8"" into kk4.4