Previous GCC7 fix was incorrect and GCC8 correctly complains about it.
Fix it properly.

Also cleaned up the Makefile for consistency between packages.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

error: memset' used with length equal to number of elements without
multiplication by element size

Signed-off-by: Rosen Penev <rosenp@gmail.com>

Signed-off-by: Martijn Zilverschoon <martijn@friedzombie.com>