[PATCH] Fix thinkos in #if -> #ifdef conversions #2

From: Tom Rini <trini@kernel.crashing.org>

And when trying to catch up on old patches, I forgot this hunk:

arch/ppc/platforms/prep_setup.c

@@ -134,6 +134,7 @@ EXPORT_SYMBOL(ppc_cs4232_dma2);
 #define PREP_IBM_CAROLINA_IDE_0	0xf0
 #define PREP_IBM_CAROLINA_IDE_1	0xf1
 #define PREP_IBM_CAROLINA_IDE_2	0xf2
+#define PREP_IBM_CAROLINA_IDE_3	0xf3
 /* 7248-43P */
 #define PREP_IBM_CAROLINA_SCSI_0	0xf4
 #define PREP_IBM_CAROLINA_SCSI_1	0xf5