n_smux: add debugfs node for printing channel states

Add debugfs node that prints detailed state information
for all smux channels.

Change-Id: I727f1c53797ee317856056b8e4d9a8686940ce0f
Signed-off-by: Brent Hronik <bhronik@codeaurora.org>
Signed-off-by: Angshuman Sarkar <angshuman@codeaurora.org>
Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile
index 9ebb54a..71f6a99 100644
--- a/drivers/tty/Makefile
+++ b/drivers/tty/Makefile
@@ -6,7 +6,7 @@
 obj-$(CONFIG_MAGIC_SYSRQ)	+= sysrq.o
 obj-$(CONFIG_N_HDLC)		+= n_hdlc.o
 obj-$(CONFIG_N_GSM)		+= n_gsm.o
-obj-$(CONFIG_N_SMUX)		+= n_smux.o
+obj-$(CONFIG_N_SMUX)		+= n_smux.o smux_debug.o
 obj-$(CONFIG_N_SMUX_LOOPBACK)	+= smux_test.o smux_loopback.o
 obj-$(CONFIG_SMUX_CTL)		+= smux_ctl.o
 obj-$(CONFIG_TRACE_ROUTER)	+= n_tracerouter.o