Test: Fix test service veneer function prefix

Some test service veneer functions are defined with "tfm_tfm_" prefix.
Fix them to "tfm_" prefix with change commit 5c61d83 in TF-M.

Signed-off-by: David Hu <david.hu@arm.com>
Change-Id: Icf3d721a91be10dcc000bb7440462d882cde694c
3 files changed