bitbake: docs: static: theme_overrides.css: fix responsive design on <640px screens

From experience the body takes the whole space anyway and the text stays
within the screen boundaries by default, no need to make the min-width
640px then.

(Bitbake rev: d52190ea426d961f609c657dcb403baf59352969)

Signed-off-by: Quentin Schulz <foss@0leil.net>
Signed-off-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/doc/sphinx-static/theme_overrides.css

@@ -4,8 +4,6 @@
 
 body {
   font-family: Verdana, Sans, sans-serif;
-
-  min-width: 640px;
   margin:  0em auto;
   color: #333;
 }