title: libcurl: how to use TPM private key for mutual SSL authentication
body: <p>I use the C libcurl library. 
  I need to do OCSP stapling combined with mutual authentication. For that, I'll take model on the below exemples. However, I need the private key of my client certificate to be stored in the TPM chip. Do you know how to do that, using tpm2-tss-engine? Thanks for your help. </p>
  
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