sh: Limit ioremap_prot() to 32bit pgprot parts.

Presently ioremap_prot() uses an unsigned long to pass the pgprot value
around. This results in the upper half of the pgprot being chomped when
using 64-bit pgprots on a 32-bit ABI (X2TLB and SH-5).

As the only users of ioremap_prot() are presently legacy parts, this
doesn't cause too much of an issue. In the future when the interface is
converted to use pgprot_t directly this can be re-enabled for the other
parts, too.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h
index c32a556..4bad72a 100644
--- a/arch/sh/include/asm/io.h
+++ b/arch/sh/include/asm/io.h
@@ -321,11 +321,13 @@
 	return __ioremap_mode(offset, size, PAGE_KERNEL);
 }
 
+#ifdef CONFIG_HAVE_IOREMAP_PROT
 static inline void __iomem *
 ioremap_prot(resource_size_t offset, unsigned long size, unsigned long flags)
 {
 	return __ioremap_mode(offset, size, __pgprot(flags));
 }
+#endif
 
 #define ioremap_nocache	ioremap
 #define iounmap		__iounmap