tpm2_getekcertificate: support ECC keys
tpm2_getekcertificate: support ECC keys

Signed-off-by: Matthew Dempsky <f80d0ca101e967b50b730ddf8e8aca0de85e8df6@dempsky.org>

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