[ALSA] Remove IRQF_DISABLED for shared PCI irqs

Fix IRQ flags for PCI devices.
The shared IRQs for PCI devices shouldn't be allocated with
IRQF_DISABLED.  Also, when MSI is enabled, IRQF_SHARED shouldn't
be used.
The patch removes unnecessary cast in request_irq and free_irq,
too.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/pci/bt87x.c b/sound/pci/bt87x.c
index 05e0091..c3f3da2 100644
--- a/sound/pci/bt87x.c
+++ b/sound/pci/bt87x.c
@@ -747,7 +747,7 @@
 	snd_bt87x_writel(chip, REG_INT_MASK, 0);
 	snd_bt87x_writel(chip, REG_INT_STAT, MY_INTERRUPTS);
 
-	if (request_irq(pci->irq, snd_bt87x_interrupt, IRQF_DISABLED | IRQF_SHARED,
+	if (request_irq(pci->irq, snd_bt87x_interrupt, IRQF_SHARED,
 			"Bt87x audio", chip)) {
 		snd_bt87x_free(chip);
 		snd_printk(KERN_ERR "cannot grab irq\n");