fixed handling of security certificates in tpm mode
The code that handles the installation of tpm security
certificates stopped working after recent updates to
other packages
This commit updates the code to properly work with the
current system configuration
Closes-Bug: #1808163
Change-Id: I76e10cf1ed68cfeb0ce3ee560df0c34711f57af2
Signed-off-by: Paul-Emile Element <Paul-Emile.Element@windriver.com>