lib/oe/package-manager: skip processing installed-pkgs with empty globs

lib/oe/package-manager: skip processing installed-pkgs with empty globs

We can skip processing the installed-pkgs file if globs is empty.
This is the case if self.d.getVar for IMAGE_INSTALL_COMPLEMENTARY
returns an empty string. If globs is an empty string the result from
processing with empty glob in oe-pkgdata-util will always be 0 packages
to install.

Instead of return early on this we just skip and still generate the
locale archive if needed.

Signed-off-by: Claus Stovgaard <claus.stovgaard@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>