efi_loader: startup the tpm device when installing the protocol

Due to U-Boot's lazy binding mentality the TPM is probed but not properly
initialized.  The user can startup the device from the command line
e.g 'tpm2 startup TPM2_SU_CLEAR'.  However we can initialize the TPM during
the TCG protocol installation,  which is easier to use overall.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>