package.bbclass: replace rpm/debugedit with dwarfsrcfiles
Debugedit provided by rpm 4.14 is rewriting binaries in-place, and was
found to produce broken output at least for grub:
http://lists.openembedded.org/pipermail/openembedded-core/2017-November/143989.html
A replacement utility was suggested via private mail:
https://lists.fedorahosted.org/archives/list/elfutils-devel@lists.fedorahosted.org/message/VZP4G5N2ELYZEDAB3QYLXYHDGX4WMCUF/
Signed-off-by: Alexander Kanavin <alexander.kanavin@linux.intel.com>