sound: oxygen: do not try to restore nonexistent EEPROM

On cards where the EEPROM was deliberately omitted, we do not need to
try to restore the EEPROM's contents.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/oxygen/oxygen_lib.c b/sound/pci/oxygen/oxygen_lib.c
index 9a8936e..c9f2714 100644
--- a/sound/pci/oxygen/oxygen_lib.c
+++ b/sound/pci/oxygen/oxygen_lib.c
@@ -278,7 +278,11 @@
 static void oxygen_restore_eeprom(struct oxygen *chip,
 				  const struct pci_device_id *id)
 {
-	if (oxygen_read_eeprom(chip, 0) != OXYGEN_EEPROM_ID) {
+	u16 eeprom_id;
+
+	eeprom_id = oxygen_read_eeprom(chip, 0);
+	if (eeprom_id != OXYGEN_EEPROM_ID &&
+	    (eeprom_id != 0xffff || id->subdevice != 0x8788)) {
 		/*
 		 * This function gets called only when a known card model has
 		 * been detected, i.e., we know there is a valid subsystem