video: fbdev: aty: aty128fb: Replace mdelay with msleep in aty128_set_suspend

aty128_set_suspend() is never called in atomic context.

The call chains ending up at aty128_set_suspend() are:
[1] aty128_set_suspend() <- aty128_pci_suspend()
[2] aty128_set_suspend() <- aty128_do_resume() <- aty128_pci_resume()
[3] aty128_set_suspend() <- aty128_do_resume() <- aty128_early_resume()

aty128_pci_suspend() is set as ".suspend" in struct pci_driver.
aty128_pci_resume() is set as ".resume" in struct pci_driver.
aty128_early_resume() is never called.
These functions are not called in atomic context.

Despite never getting called from atomic context, aty128_set_suspend()
calls mdelay() to busily wait.
This is not necessary and can be replaced with msleep() to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

drivers/video/fbdev/aty/aty128fb.c

@@ -2442,7 +2442,7 @@ static void aty128_set_suspend(struct aty128fb_par *par, int suspend)
 		(void)aty_ld_pll(POWER_MANAGEMENT);
 		aty_st_le32(BUS_CNTL1, 0x00000010);
 		aty_st_le32(MEM_POWER_MISC, 0x0c830000);
-		mdelay(100);
+		msleep(100);
 
 		/* Switch PCI power management to D2 */
 		pci_set_power_state(pdev, PCI_D2);