Fix quoting problem (preboot setting) in many board config files.

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/include/configs/TQM860M.h b/include/configs/TQM860M.h
index 8601de1..00b7853 100644
--- a/include/configs/TQM860M.h
+++ b/include/configs/TQM860M.h
@@ -49,7 +49,7 @@
 #define CONFIG_BOARD_TYPES	1	/* support board types		*/
 
 #define CONFIG_PREBOOT	"echo;"	\
-	"echo Type \"run flash_nfs\" to mount root filesystem over NFS;" \
+	"echo Type \\\"run flash_nfs\\\" to mount root filesystem over NFS;" \
 	"echo"
 
 #undef	CONFIG_BOOTARGS