mdadm: add hash file

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/mdadm/mdadm.hash

@@ -0,0 +1,2 @@
+# From https://www.kernel.org/pub/linux/utils/raid/mdadm/sha256sums.asc
+sha256	0f3a7e1a76b13892b79f9fceaf99ecb23513260389a768ac644ffa3ae06e5b8c	mdadm-3.3.2.tar.xz