drivers/tpm/spi: Refactor out some cr50-specific logic

Mainboards accessing the cr50 over an I2C bus may want to reuse some of
the same firmware version and BOARD_CFG logic, therefore refactor this
logic out into a bus-agnostic file, drivers/tpm/cr50.c. This file uses
the new tis_vendor_read/write() functions in order to access the cr50
regardless of the bus which is physically used. In order to leave SPI
devices intact, the tis_vendor_* functions are added to the SPI driver.

BUG=b:202246591
TEST=boot to OS on google/dratini, see the same FW version and board_cfg
console prints as before the change.

Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: Ie68618cbe026a2b9221f93d0fe41d0b2054e8091
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61977
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>

src/drivers/tpm/cr50.h

@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef __DRIVERS_TPM_CR50_H__
+#define __DRIVERS_TPM_CR50_H__
+
+#include <types.h>
+
+/* Structure describing the elements of Cr50 firmware version. */
+struct cr50_firmware_version {
+	int epoch;
+	int major;
+	int minor;
+};
+
+/* Indicates whether Cr50 ready pulses are guaranteed to be at least 100us. */
+bool cr50_is_long_interrupt_pulse_enabled(void);
+
+/* Get the Cr50 firmware version information. */
+cb_err_t cr50_get_firmware_version(struct cr50_firmware_version *version);
+
+/* Set the BOARD_CFG register depending on Cr50 Kconfigs */
+cb_err_t cr50_set_board_cfg(void);
+
+#endif /* __DRIVERS_TPM_CR50_H__ */