Rather than setting the size of the TPM buffer in the front-end,
query the backend for the size of the buffer. In this patch we
just move the hard-coded buffer size of 4096 to the backends.
Signed-off-by: NStefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>