m68k: dmasound - Kill warn_unused_result warnings

warning: ignoring return value of 'request_irq', declared with attribute
warn_unused_result

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
diff --git a/sound/oss/dmasound/dmasound_atari.c b/sound/oss/dmasound/dmasound_atari.c
index 4d45bd6..57d9f15 100644
--- a/sound/oss/dmasound/dmasound_atari.c
+++ b/sound/oss/dmasound/dmasound_atari.c
@@ -851,8 +851,9 @@
 	mfp.tim_dt_a = 1;	/* Cause interrupt after first event. */
 	mfp.tim_ct_a = 8;	/* Turn on event counting. */
 	/* Register interrupt handler. */
-	request_irq(IRQ_MFP_TIMA, AtaInterrupt, IRQ_TYPE_SLOW, "DMA sound",
-		    AtaInterrupt);
+	if (request_irq(IRQ_MFP_TIMA, AtaInterrupt, IRQ_TYPE_SLOW, "DMA sound",
+			AtaInterrupt))
+		return 0;
 	mfp.int_en_a |= 0x20;	/* Turn interrupt on. */
 	mfp.int_mk_a |= 0x20;
 	return 1;