tpm: fix tpm_acpi sparse warning on different address spaces

acpi_os_map_memory expects its return value to be in the __iomem address
space. Tag the variable we're using as such and use memcpy_fromio to
avoid further sparse warnings.
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

drivers/char/tpm/tpm_acpi.c

@@ -49,7 +49,7 @@ int read_log(struct tpm_bios_log *log)
 {
 	struct acpi_tcpa *buff;
 	acpi_status status;
-	struct acpi_table_header *virt;
+	void __iomem *virt;
 	u64 len, start;
 
 	if (log->bios_event_log != NULL) {
@@ -102,7 +102,7 @@ int read_log(struct tpm_bios_log *log)
 		return -EIO;
 	}
 
-	memcpy(log->bios_event_log, virt, len);
+	memcpy_fromio(log->bios_event_log, virt, len);
 
 	acpi_os_unmap_memory(virt, len);
 	return 0;