deb-pkg: Use $SRCARCH for include path
Fix x86 centric path to allow building kernel-header packages for
other architecture.
Signed-off-by: maximilian attems <max@stro.at>
Signed-off-by: Michal Marek <mmarek@suse.cz>
authored by maximilian attems and committed by Michal Marek 1b9a50d9 ee81b786