FAPI: Fix missing check of pathname used for imported policies.
FAPI: Fix missing check of pathname used for imported policies.

It was not checked whether the pathname for imported policies, which will be
used for the policy store, did contain invalid characters.

Signed-off-by: Juergen Repp <03d74050f14a4f4ffcef98e77db067d01b35ed27@sit.fraunhofer.de>

01org/tpm2-tss,01org/tpm2-tss,tpm2-software/tpm2-tss,01org/TPM2.0-TSS,01org/TPM2.0-TSS,01org/TPM2.0-TSS,tpm2-software/tpm2-tss,01org/tpm2-tss,01org/TPM2.0-TSS,tpm2-software/tpm2-tss