block: enable libnfs on msys2/mingw in cirrus.yml

Initially, libnfs has not been enabled, and now it's fixed, so enable it
on cirrus.

Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Message-Id: <20201105123116.674-3-luoyonggang@gmail.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
1 file changed