Fix MISRA rule 8.5 in common code
Fix MISRA rule 8.5 in common code

Rule 8.5: An external object or function shall be declared
          once in one and only one file.

Change-Id: I7c3d4ec7d3ba763fdb4600008ba10b4b93ecdfce
Signed-off-by: Roberto Vargas <d75e640c49defb97bd074f828210df57ed181e1f@arm.com>

achingupta/arm-trusted-firmware,achingupta/arm-trusted-firmware