net-caif-driver: add CAIF serial driver (ldisc)

Add CAIF Serial driver. This driver is implemented as a line discipline.

caif_serial uses the following module parameters:
ser_use_stx - specifies if STart of frame eXtension is in use.
ser_loop    - sets the interface in loopback mode.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/caif/Makefile b/drivers/net/caif/Makefile
new file mode 100644
index 0000000..52b6d1f
--- /dev/null
+++ b/drivers/net/caif/Makefile
@@ -0,0 +1,12 @@
+ifeq ($(CONFIG_CAIF_DEBUG),1)
+CAIF_DBG_FLAGS := -DDEBUG
+endif
+
+KBUILD_EXTRA_SYMBOLS=net/caif/Module.symvers
+
+ccflags-y := $(CAIF_FLAGS) $(CAIF_DBG_FLAGS)
+clean-dirs:= .tmp_versions
+clean-files:= Module.symvers modules.order *.cmd *~ \
+
+# Serial interface
+obj-$(CONFIG_CAIF_TTY) += caif_serial.o