lcd: Implement RLE8 bitmap decoding

Add support for drawing compressed RLE8 bitmaps.

Reference: http://www.digicamsoft.com/bmp/bmp.html

Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Tom Wai-Hong Tam <waihong@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Che-Liang Chiou <clchiou@chromium.org>
[agust: fix some minor style issues and build warnings]
Signed-off-by: Anatolij Gustschin <agust@denx.de>
diff --git a/README b/README
index afdf591..2dc0984 100644
--- a/README
+++ b/README
@@ -1469,6 +1469,11 @@
 		Normally display is black on white background; define
 		CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
 
+		CONFIG_LCD_BMP_RLE8
+
+		Support drawing of RLE8-compressed bitmaps on the LCD.
+
+
 - Splash Screen Support: CONFIG_SPLASH_SCREEN
 
 		If this option is set, the environment is checked for