efi_loader: use tpm_auto_start for the tpm device

A previous commit is adding a new tpm startup functions which
initializes the TPMv2 and performs all the needed selftests.
Since the TPM selftests might be needed depending on the requested
algorithm or functional module use that instead.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>