Limit selected PCRs to 8
Limit selected PCRs to 8

When a PCR selection has more than 8 selections, the pcrSelections
array was being indexed past its end.

Fixes: #778

Signed-off-by: William Roberts <60148e894dabf0b83bde1d460768794cd453c455@intel.com>

01org/tpm2.0-tools,01org/tpm2.0-tools,martinezjavier/tpm2-tools,martinezjavier/tpm2-tools,martinezjavier/tpm2-tools,01org/tpm2.0-tools,martinezjavier/tpm2-tools