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/lib_generic/lzo/lzodefs.h b/lib_generic/lzo/lzodefs.h
new file mode 100644
index 0000000..b6d482c
--- /dev/null
+++ b/lib_generic/lzo/lzodefs.h
@@ -0,0 +1,43 @@
+/*
+ *  lzodefs.h -- architecture, OS and compiler specific defines
+ *
+ *  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 LZO_VERSION		0x2020
+#define LZO_VERSION_STRING	"2.02"
+#define LZO_VERSION_DATE	"Oct 17 2005"
+
+#define M1_MAX_OFFSET	0x0400
+#define M2_MAX_OFFSET	0x0800
+#define M3_MAX_OFFSET	0x4000
+#define M4_MAX_OFFSET	0xbfff
+
+#define M1_MIN_LEN	2
+#define M1_MAX_LEN	2
+#define M2_MIN_LEN	3
+#define M2_MAX_LEN	8
+#define M3_MIN_LEN	3
+#define M3_MAX_LEN	33
+#define M4_MIN_LEN	3
+#define M4_MAX_LEN	9
+
+#define M1_MARKER	0
+#define M2_MARKER	64
+#define M3_MARKER	32
+#define M4_MARKER	16
+
+#define D_BITS		14
+#define D_MASK		((1u << D_BITS) - 1)
+#define D_HIGH		((D_MASK >> 1) + 1)
+
+#define DX2(p, s1, s2)	(((((size_t)((p)[2]) << (s2)) ^ (p)[1]) \
+							<< (s1)) ^ (p)[0])
+#define DX3(p, s1, s2, s3)	((DX2((p)+1, s2, s3) << (s1)) ^ (p)[0])