Remove link to downloads for Factory image HiKey620

Under installation section, the Factory image
option had a link to downloads. This link was
removed to prevent confusion. Link to Linux
installation option should be the only
option for this method.

Signed-off-by: Robert Wolff <robert.wolff@linaro.org>

consumer/hikey/hikey620/installation/README.md

@@ -59,8 +59,6 @@ This method requires the following hardware:
 - USB to microUSB cable
 - HDMI Monitor with full size HDMI cable (not required to perform flash)
 
-Go to the [Downloads page](../downloads/) to get your Factory Image zip file.
-
 Choose host machine
 
 - [Linux](linux-factory-image.md)