can: dev: move driver related infrastructure into separate subdir

This patch moves the CAN driver related infrastructure into a separate subdir.
It will be split into more files in the coming patches.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/Makefile

@@ -7,12 +7,7 @@ obj-$(CONFIG_CAN_VCAN)		+= vcan.o
 obj-$(CONFIG_CAN_VXCAN)		+= vxcan.o
 obj-$(CONFIG_CAN_SLCAN)		+= slcan.o
 
-obj-$(CONFIG_CAN_DEV)		+= can-dev.o
+obj-y				+= dev/
-can-dev-y			+= dev.o
-can-dev-y			+= rx-offload.o
-
-can-dev-$(CONFIG_CAN_LEDS)	+= led.o
-
 obj-y				+= rcar/
 obj-y				+= spi/
 obj-y				+= usb/

drivers/net/can/dev/Makefile

@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_CAN_DEV)		+= can-dev.o
+can-dev-y			+= dev.o
+can-dev-y			+= rx-offload.o
+
+can-dev-$(CONFIG_CAN_LEDS)	+= led.o