tpm: replace tpm_gen_interrupt() with tpm_tis_gen_interrupt()

Since tpm_gen_interrupt() is only used in tpm_tis_core.c this commit
replaces it with an internal tpm_tis_gen_interrupt(). The semantics
also changed in a way that on a system error the driver initialization
is failed.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

drivers/char/tpm/tpm2-cmd.c

@@ -736,6 +736,7 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
 
 	return rc;
 }
+EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
 
 #define TPM2_STARTUP_IN_SIZE \
 	(sizeof(struct tpm_input_header) + \
@@ -923,23 +924,6 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
 	return rc;
 }
 
-/**
- * tpm2_gen_interrupt() - generate an interrupt
- * @chip: TPM chip to use
- *
- * 0 is returned when the operation is successful. If a negative number is
- * returned it remarks a POSIX error code. If a positive number is returned
- * it remarks a TPM error.
- */
-int tpm2_gen_interrupt(struct tpm_chip *chip)
-{
-	u32 dummy;
-
-	return tpm2_get_tpm_pt(chip, 0x100, &dummy,
-			       "attempting to generate an interrupt");
-}
-EXPORT_SYMBOL_GPL(tpm2_gen_interrupt);
-
 /**
  * tpm2_probe() - probe TPM 2.0
  * @chip: TPM chip to use