ALSA: PCI: Replace CONFIG_PM with CONFIG_PM_SLEEP

Otherwise we may get compile warnings due to unused functions.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/cs46xx/cs46xx.h b/sound/pci/cs46xx/cs46xx.h
index 29d8a8d..fc339ef 100644
--- a/sound/pci/cs46xx/cs46xx.h
+++ b/sound/pci/cs46xx/cs46xx.h
@@ -1721,7 +1721,7 @@
 	unsigned int play_ctl;
 #endif
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 	u32 *saved_regs;
 #endif
 };