[ALSA] cmipci - Disable integrated mpu401 as default

Enable the support of mpu401 PCI port only when mpu_port=1 module
option is given, i.e. disabled as default.
It turned out that the check of integrated midi port isn't perfect
and caused hang-ups on some boards.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

Documentation/sound/alsa/ALSA-Configuration.txt

@@ -366,7 +366,9 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
 
     Module for C-Media CMI8338 and 8738 PCI sound cards.
 
-    mpu_port	- 0x300,0x310,0x320,0x330, 0 = disable (default)
+    mpu_port	- 0x300,0x310,0x320,0x330 = legacy port,
+		  1 = integrated PCI port,
+		  0 = disable (default)
     fm_port     - 0x388 (default), 0 = disable (default)
     soft_ac3    - Software-conversion of raw SPDIF packets (model 033 only)
                   (default = 1)

sound/pci/cmipci.c

@@ -2932,7 +2932,7 @@ static int __devinit snd_cmipci_create(struct snd_card *card, struct pci_dev *pc
 	}
 
 	integrated_midi = snd_cmipci_read_b(cm, CM_REG_MPU_PCI) != 0xff;
-	if (integrated_midi)
+	if (integrated_midi && mpu_port[dev] == 1)
 		iomidi = cm->iobase + CM_REG_MPU_PCI;
 	else {
 		iomidi = mpu_port[dev];