tpm: st33zp24: Add tpm st33zp24 support with i2c

Add support for TPM ST33ZP24 family with i2c.

For i2c we are relying only on DM_I2C.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
diff --git a/README b/README
index 864c7cc..ec73a4e 100644
--- a/README
+++ b/README
@@ -1423,6 +1423,13 @@
 			CONFIG_TPM_TIS_I2C_BURST_LIMITATION
 			Define the burst count bytes upper limit
 
+		CONFIG_TPM_ST33ZP24
+		Support for STMicroelectronics TPM devices. Requires DM_TPM support.
+
+			CONFIG_TPM_ST33ZP24_I2C
+			Support for STMicroelectronics ST33ZP24 I2C devices.
+			Requires TPM_ST33ZP24 and I2C.
+
 		CONFIG_TPM_ATMEL_TWI
 		Support for Atmel TWI TPM device. Requires I2C support.