The companion debug filesystem contains only the package database and the
complementary *-dbg packages for the main filesystem component.  This is
useful in a production environment to produce a companion filesystem capable
of remote system debugging, without requiring corresponding debug symbols or
source code on the device.

Signed-off-by: Mark Hatle <mark.hatle@windriver.com>
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>

If dbg pkgs have already been installed to the rootfs image,
the installation to companion debug filesystem will fail,
because both of image creation make use of the same pm
database.

In this situation, try to copy installed dbg files from rootfs
image to companion debug filesystem.

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Mark Hatle <mark.hatle@windriver.com>