Fix build error with correct format string
Fix build error with correct format string

Change-Id: I11c12b113c4975efd3ac7ac2e8b93e6771a7e7ff
Signed-off-by: Jeenu Viswambharan <5b289de972918ffd274229d00560f010009baf9e@arm.com>

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