drivers/spi/tpm/tpm.c: Use __func__

Change-Id: I8a8b0575689d7b63fd37edc457abc42710a13e97
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/49552
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Christian Walter <christian.walter@9elements.com>
diff --git a/src/drivers/spi/tpm/tpm.c b/src/drivers/spi/tpm/tpm.c
index d65decda..1ad1eaa 100644
--- a/src/drivers/spi/tpm/tpm.c
+++ b/src/drivers/spi/tpm/tpm.c
@@ -74,7 +74,8 @@
 	static int warning_displayed;
 
 	if (!warning_displayed) {
-		printk(BIOS_WARNING, "WARNING: tis_plat_irq_status() not implemented, wasting 10ms to wait on Cr50!\n");
+		printk(BIOS_WARNING, "WARNING: %s() not implemented, wasting 10ms to wait on"
+		       " Cr50!\n", __func__);
 		warning_displayed = 1;
 	}
 	mdelay(10);