Slight refactoring

- there should be 2 blank after the header guard/copyright comments and before the header guard ending

Change-Id: Ia49041ba0b96af9678371866c789805da0c0dff3
Reviewed-on: https://review.haiku-os.org/c/haiku/+/10578
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: Adrien Destugues <[email protected]>
Haiku-Format: Haiku-format Bot <[email protected]>

headers/os/drivers/device_manager.h

@@ -37,6 +37,7 @@ typedef struct {
 		 */
 } io_resource;
 
+
 /* attribute of a device node */
 typedef struct {
 	const char		*name;
@@ -187,4 +188,5 @@ struct device_module_info {
 	status_t (*deselect)(void *cookie, uint8 event, selectsync *sync);
 };
 
+
 #endif	/* _DEVICE_MANAGER_H */