tpm: add AUTH1 cmds for LoadKey2 and GetPubKey

Extend the tpm library with support for single authorized (AUTH1) commands
as specified in the TCG Main Specification 1.2. (The internally used helper
functions are implemented in a way that they could also be used for double
authorized commands if someone needs it.)

Provide enums with the return codes from the TCG Main specification.

For now only a single OIAP session is supported.

OIAP authorized version of the commands TPM_LoadKey2 and TPM_GetPubKey are
provided. Both features are available using the 'tpm' command, too.

Authorized commands are enabled with CONFIG_TPM_AUTH_SESSIONS. (Note that
this also requires CONFIG_SHA1 to be enabled.)

Signed-off-by: Reinhard Pfau <reinhard.pfau@gdsys.cc>
Signed-off-by: Dirk Eibach <dirk.eibach@gdsys.cc>
Acked-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Andy Fleming <afleming@freescale.com>
diff --git a/README b/README
index 33b5728..3941725 100644
--- a/README
+++ b/README
@@ -1247,6 +1247,20 @@
 			to. Contemporary x86 systems usually map it at
 			0xfed40000.
 
+		CONFIG_CMD_TPM
+		Add tpm monitor functions.
+		Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
+		provides monitor access to authorized functions.
+
+		CONFIG_TPM
+		Define this to enable the TPM support library which provides
+		functional interfaces to some TPM commands.
+		Requires support for a TPM device.
+
+		CONFIG_TPM_AUTH_SESSIONS
+		Define this to enable authorized functions in the TPM library.
+		Requires CONFIG_TPM and CONFIG_SHA1.
+
 - USB Support:
 		At the moment only the UHCI host controller is
 		supported (PIP405, MIP405, MPC5200); define