dnrd: fix SRC_URI

Fixed:
ERROR: Function failed: Fetcher failure for URL:
    'http://ncu.dl.sourceforge.net/project/dnrd/dnrd/2.20.3/dnrd-2.20.3.tar.gz

'.
    Unable to fetch URL from any source.

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Joe MacDonald <joe_macdonald@mentor.com>