coresight: Make coresight functions as inline

Make coresight_disable_all_source_link and
coresight_enable_all_source_link as inline to resolve
compilation failure when coresight is disabled.

Change-Id: Ibc535b785f7393041ca82d0777ab489d8f48e03c
Signed-off-by: Archana Sriram <apsrir@codeaurora.org>