sh: Fix up uncached offset for legacy 29-bit mode.

The uncached_start was being set up properly for 32-bit but managed to
break 29-bit in the process, fix it up.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/mm/uncached.c

 #include <linux/init.h>
 #include <asm/sizes.h>
 #include <asm/page.h>
+#include <asm/addrspace.h>
 
 /*
  * This is the offset of the uncached section from its cached alias.
@@ -23,7 +24,11 @@ int virt_addr_uncached(unsigned long kaddr)
 
 void __init uncached_init(void)
 {
+#ifdef CONFIG_29BIT
+	uncached_start = P2SEG;
+#else
 	uncached_start = memory_end;
+#endif
 	uncached_end = uncached_start + uncached_size;
 }