peci: constify the struct device_type usage

Since commit aed65af1cc2f ("drivers: make device_type const"), the driver
core can properly handle constant struct device_type. Move the
peci_controller_type and peci_device_type variables to be constant
structures as well, placing it into read-only memory which can not be
modified at runtime.

Cc: Greg Kroah-Hartman <[e-mail]>
Signed-off-by: "Ricardo B. Marliere" <[e-mail]>
Reviewed-by: Iwona Winiarska <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Iwona Winiarska <[e-mail]>

drivers/peci/core.c

···
 	kfree(controller);
 }
 
-struct device_type peci_controller_type = {
+const struct device_type peci_controller_type = {
 	.release	= peci_controller_dev_release,
 };
 

drivers/peci/device.c

···
 	kfree(device);
 }
 
-struct device_type peci_device_type = {
+const struct device_type peci_device_type = {
 	.groups		= peci_device_groups,
 	.release	= peci_device_release,
 };

drivers/peci/internal.h

···
 	u8 model;
 };
 
-extern struct device_type peci_device_type;
+extern const struct device_type peci_device_type;
 extern const struct attribute_group *peci_device_groups[];
 
 int peci_device_create(struct peci_controller *controller, u8 addr);
···
 #define module_peci_driver(__peci_driver) \
 	module_driver(__peci_driver, peci_driver_register, peci_driver_unregister)
 
-extern struct device_type peci_controller_type;
+extern const struct device_type peci_controller_type;
 
 int peci_controller_scan_devices(struct peci_controller *controller);