Update MTD to that of Linux 2.6.22.1

A lot changed in the Linux MTD code, since it was last ported from
Linux to U-Boot. This patch takes U-Boot NAND support to the level
of Linux 2.6.22.1 and will enable support for very large NAND devices
(4KB pages) and ease the compatibility between U-Boot and Linux
filesystems.

This patch is tested on two custom boards with PPC and ARM
processors running YAFFS in U-Boot and Linux using gcc-4.1.2
cross compilers.

MAKEALL ppc/arm has some issues:
 * DOC/OneNand/nand_spl is not building (I have not tried porting
   these parts, and since I do not have any HW and I am not familiar
   with this code/HW I think its best left to someone else.)

Except for the issues mentioned above, I have ported all drivers
necessary to run MAKEALL ppc/arm without errors and warnings. Many
drivers were trivial to port, but some were not so trivial. The
following drivers must be examined carefully and maybe rewritten to
some degree:
 cpu/ppc4xx/ndfc.c
 cpu/arm926ejs/davinci/nand.c
 board/delta/nand.c
 board/zylonite/nand.c

Signed-off-by: William Juul <william.juul@tandberg.com>
Signed-off-by: Stig Olsen <stig.olsen@tandberg.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
diff --git a/include/linux/err.h b/include/linux/err.h
new file mode 100644
index 0000000..4e08c4f
--- /dev/null
+++ b/include/linux/err.h
@@ -0,0 +1,45 @@
+#ifndef _LINUX_ERR_H
+#define _LINUX_ERR_H
+
+/* XXX U-BOOT XXX */
+#if 0
+#include <linux/compiler.h>
+#else
+#include <linux/mtd/compat.h>
+#endif
+
+#include <asm/errno.h>
+
+
+/*
+ * Kernel pointers have redundant information, so we can use a
+ * scheme where we can return either an error code or a dentry
+ * pointer with the same return value.
+ *
+ * This should be a per-architecture thing, to allow different
+ * error and pointer decisions.
+ */
+#define MAX_ERRNO	4095
+
+#ifndef __ASSEMBLY__
+
+#define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO)
+
+static inline void *ERR_PTR(long error)
+{
+	return (void *) error;
+}
+
+static inline long PTR_ERR(const void *ptr)
+{
+	return (long) ptr;
+}
+
+static inline long IS_ERR(const void *ptr)
+{
+	return IS_ERR_VALUE((unsigned long)ptr);
+}
+
+#endif
+
+#endif /* _LINUX_ERR_H */