ALSA: ad1889: Replace mdelay with usleep_range in snd_ad1889_init

snd_ad1889_init() is never called in atomic context.

The call chain ending up at snd_ad1889_init() is:
[1] snd_ad1889_init() <- snd_ad1889_create() <- snd_ad1889_probe()

snd_ad1889_probe() is only set as ".probe" in struct pci_driver.
This function is not called in atomic context.

Despite never getting called from atomic context, snd_ad1889_init()
calls mdelay for busy wait.
This is not necessary and can be replaced with usleep_range to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/ad1889.c

@@ -872,7 +872,7 @@ snd_ad1889_init(struct snd_ad1889 *chip)
 	ad1889_writew(chip, AD_DS_CCS, AD_DS_CCS_CLKEN); /* turn on clock */
 	ad1889_readw(chip, AD_DS_CCS);	/* flush posted write */
 
-	mdelay(10);
+	usleep_range(10000, 11000);
 
 	/* enable Master and Target abort interrupts */
 	ad1889_writel(chip, AD_DMA_DISR, AD_DMA_DISR_PMAE | AD_DMA_DISR_PTAE);