tpm: add Revision ID field in the chip structure

TPM are shipped with a few read-only register from which we can retrieve
for instance:
- vendor ID
- product ID
- revision ID

Product and vendor ID share the same register and are already referenced
in the tpm_chip structure. Add the revision ID entry which is missing.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/tpm/tpm_tis.h b/drivers/tpm/tpm_tis.h
index a899bc0..947585f 100644
--- a/drivers/tpm/tpm_tis.h
+++ b/drivers/tpm/tpm_tis.h
@@ -40,6 +40,7 @@
 	int is_open;
 	int locality;
 	u32 vend_dev;
+	u8 rid;
 	unsigned long timeout_a, timeout_b, timeout_c, timeout_d;  /* msec */
 	ulong chip_type;
 };