image.bbclass: preserve debugfs tarball with checksum fstype

image.bbclass: preserve debugfs tarball with checksum fstype

Previously, when adding checksum fstypes to IMAGE_FSTYPES_DEBUGFS, e.g.
IMAGE_FSTYPES_DEBUGFS = "tar.bz2 tar.bz2.sha256sum", only the checksum
file remained in DEPLOY_DIR while the tarball file was removed. The
underlying issue was that inside gen_conversion_cmds, removing the
debugfs_ prefix from type broke the comparison with alltypes where the
prefix was expected.

Signed-off-by: Manuel Leonhardt <mleonhardt@arri.de>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>