ARM: cache-l2x0: get size of outer cache

ARM: cache-l2x0: get size of outer cache

Implement interface for getting size of outer cache.

bug 983964

Change-Id: If855f32d3eaa4c673c132b1964a46fe1c15b4dfe
Signed-off-by: Kirill Artamonov <kartamonov@nvidia.com>
Reviewed-on: http://git-master/r/140024
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Reviewed-by: Sachin Nikam <snikam@nvidia.com>
Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>
Rebase-Id: R11f28e4f625d2626a7a9270265a485e9b07c473f