add lzop decompression support

Add lzop decompression support to the existing lzo bitstream handling
(think gzip versus zlib), and support it for uImage decompression if
CONFIG_LZO is enabled.

Lzop doesn't compress as good as gzip (~10% worse), but decompression
is very fast (~0.7s faster here on a slow ppc). The lzop decompression
code is based on Albin Tonnerre's recent ARM Linux lzo support patch.

Cc: albin.tonnerre@free-electrons.com
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
diff --git a/include/image.h b/include/image.h
index 5a424e6..cc38eae 100644
--- a/include/image.h
+++ b/include/image.h
@@ -164,6 +164,7 @@
 #define IH_COMP_GZIP		1	/* gzip	 Compression Used	*/
 #define IH_COMP_BZIP2		2	/* bzip2 Compression Used	*/
 #define IH_COMP_LZMA		3	/* lzma  Compression Used	*/
+#define IH_COMP_LZO		4	/* lzo   Compression Used	*/
 
 #define IH_MAGIC	0x27051956	/* Image Magic Number		*/
 #define IH_NMLEN		32	/* Image Name Length		*/