This implements pkgtype into .PKGINFO. This is useful to ensure tools
parsing packages do not miss important context on the creation of the
package.
For instance discovering if a given .pkg.tar is a debug package, one
would have to do heuristics on the pkgdesc and "${pkgbase}-debug".
However both of these values are controlled by the packager.
Similarly, the heuristic for discovering split packages is if pkgbase
and pkgname differ, which can happen in any package as both values are
packager controlled.
This should ensure we don't need to rely on heuristics and instead
include the context of how the package was created.
Signed-off-by: Morten Linderud <morten@linderud.pw>
Signed-off-by: Allan McRae <allan@archlinux.org>