tpm: Untangle tpm2_get_pcr_info()

tpm: Untangle tpm2_get_pcr_info()

This function was used on measured boot to retrieve the number of active
PCR banks and was designed to work with the TCG protocols.
Since we now have the need to retrieve the active PCRs outside the
measured boot context -- e.g use the in the command line, decouple the
function.

Create one that will only adheres to TCG TSS2.0 [0] specification called
tpm2_get_pcr_info() which can be used by the TPM2.0 APIs and a new one that
is called from the measured boot context called tcg2_get_pcr_info()

[0] https://trustedcomputinggroup.org/wp-content/uploads/TSS_Overview_Common_Structures_Version-0.9_Revision-03_Review_030918.pdf

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>