hdrpackage and headerpackage are not intuitive names,
use proposed alternatives by Michel Marek.

While touching them move the mkdir of the kernel_headers dir up
and fix it for paranoid umask.

CC: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Nmaximilian attems <max@stro.at>
Signed-off-by: NMichal Marek <mmarek@suse.cz>