can: flexcan: move driver into separate sub directory

This patch moves the flexcan driver into a separate directory, a later
patch will add more files.

Link: https://lore.kernel.org/all/20220107193105.1699523-2-mkl@pengutronix.deSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/Makefile

@@ -16,7 +16,7 @@ obj-y				+= softing/
 obj-$(CONFIG_CAN_AT91)		+= at91_can.o
 obj-$(CONFIG_CAN_CC770)		+= cc770/
 obj-$(CONFIG_CAN_C_CAN)		+= c_can/
-obj-$(CONFIG_CAN_FLEXCAN)	+= flexcan.o
+obj-$(CONFIG_CAN_FLEXCAN)	+= flexcan/
 obj-$(CONFIG_CAN_GRCAN)		+= grcan.o
 obj-$(CONFIG_CAN_IFI_CANFD)	+= ifi_canfd/
 obj-$(CONFIG_CAN_JANZ_ICAN3)	+= janz-ican3.o

drivers/net/can/flexcan/Makefile

+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_CAN_FLEXCAN) += flexcan.o
+
+flexcan-objs :=
+flexcan-objs += flexcan-core.o