bus: uniphier-system-bus: fix condition of overlap check

This patch fixes condition whether the specified address ranges
overlap each other.

Fixes: 4b7f48d3 ("bus: uniphier-system-bus: add UniPhier System Bus driver")
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Olof Johansson <olof@lixom.net>