[ALSA] Add snd-portman2x4 driver for Midiman Portman 2x4 MIDI device

snd-portman2x4 driver supports Midiman Portman 2x4 parallel port
MIDI device.

Signed-off-by: Matthias Koenig <mkoenig@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/drivers/Makefile b/sound/drivers/Makefile
index c9bad6d..0411264 100644
--- a/sound/drivers/Makefile
+++ b/sound/drivers/Makefile
@@ -6,6 +6,7 @@
 snd-dummy-objs := dummy.o
 snd-mtpav-objs := mtpav.o
 snd-mts64-objs := mts64.o
+snd-portman2x4-objs := portman2x4.o
 snd-serial-u16550-objs := serial-u16550.o
 snd-virmidi-objs := virmidi.o
 
@@ -15,5 +16,6 @@
 obj-$(CONFIG_SND_SERIAL_U16550) += snd-serial-u16550.o
 obj-$(CONFIG_SND_MTPAV) += snd-mtpav.o
 obj-$(CONFIG_SND_MTS64) += snd-mts64.o
+obj-$(CONFIG_SND_PORTMAN2X4) += snd-portman2x4.o
 
 obj-$(CONFIG_SND) += opl3/ opl4/ mpu401/ vx/