sparc32: fix warning in floopy glue

Fix following warning:
arch/sparc/include/asm/floppy_32.h:342:5: warning: 'op' may be used uninitialized in this function

The warning are legitimite and we can end up using op uninitialized.
This fixes build with my gcc on UP.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/include/asm/floppy_32.h b/arch/sparc/include/asm/floppy_32.h
index f954856..491eb68 100644
--- a/arch/sparc/include/asm/floppy_32.h
+++ b/arch/sparc/include/asm/floppy_32.h
@@ -334,6 +334,7 @@
 	/* Look up irq in platform_device.
 	 * We try "SUNW,fdtwo" and "fd"
 	 */
+	op = NULL;
 	for_each_node_by_name(dp, "SUNW,fdtwo") {
 		op = of_find_device_by_node(dp);
 		if (op)