Add LZO decompressor support

This patch adds LZO decompression support to U-Boot. It is needed for
the upcoming UBIFS support, since UBIFS uses LZO as default compressor/
decompressor. Since we only support read-only in UBIFS, only the
decompressor is needed.

All this is copied with minor changes from the current Linux kernel
version (2.6.28-rc8).

This patch only implements this LZO decompressor support for PPC.
Other platforms using UBIFS will have to add the required
"include/asm/unaligned.h" as well. It should be fairly easy to copy this
from the Linux source tree as I have done it for PPC in this patch.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/include/linux/lzo.h b/include/linux/lzo.h
new file mode 100644
index 0000000..d793497
--- /dev/null
+++ b/include/linux/lzo.h
@@ -0,0 +1,44 @@
+#ifndef __LZO_H__
+#define __LZO_H__
+/*
+ *  LZO Public Kernel Interface
+ *  A mini subset of the LZO real-time data compression library
+ *
+ *  Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
+ *
+ *  The full LZO package can be found at:
+ *  http://www.oberhumer.com/opensource/lzo/
+ *
+ *  Changed for kernel use by:
+ *  Nitin Gupta <nitingupta910@gmail.com>
+ *  Richard Purdie <rpurdie@openedhand.com>
+ */
+
+#define LZO1X_MEM_COMPRESS	(16384 * sizeof(unsigned char *))
+#define LZO1X_1_MEM_COMPRESS	LZO1X_MEM_COMPRESS
+
+#define lzo1x_worst_compress(x) ((x) + ((x) / 16) + 64 + 3)
+
+/* This requires 'workmem' of size LZO1X_1_MEM_COMPRESS */
+int lzo1x_1_compress(const unsigned char *src, size_t src_len,
+			unsigned char *dst, size_t *dst_len, void *wrkmem);
+
+/* safe decompression with overrun testing */
+int lzo1x_decompress_safe(const unsigned char *src, size_t src_len,
+			unsigned char *dst, size_t *dst_len);
+
+/*
+ * Return values (< 0 = Error)
+ */
+#define LZO_E_OK			0
+#define LZO_E_ERROR			(-1)
+#define LZO_E_OUT_OF_MEMORY		(-2)
+#define LZO_E_NOT_COMPRESSIBLE		(-3)
+#define LZO_E_INPUT_OVERRUN		(-4)
+#define LZO_E_OUTPUT_OVERRUN		(-5)
+#define LZO_E_LOOKBEHIND_OVERRUN	(-6)
+#define LZO_E_EOF_NOT_FOUND		(-7)
+#define LZO_E_INPUT_NOT_CONSUMED	(-8)
+#define LZO_E_NOT_YET_IMPLEMENTED	(-9)
+
+#endif