plat/arm: remove common code for soc-id feature

Removed common code for soc-id feature which is applicable
for all arm platforms.

In subsequent patches, added a platform based functions
for FVP and Juno to retrieve the soc-id information.

Change-Id: Idb632a935758a6caff2ca03a6eab8f663da8a93a
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
1 file changed