Revert "Stop converting relative symlinks to absolute."

This reverts commit 9ae3638429.

This change is ok, but cannot be used right now because all existing
binpkgs were created with an old xbps-create(8).

NEWS

@@ -3,9 +3,7 @@ xbps-0.44 (???):
  * xbps-pkgdb(8): this now uses the code from libxbps to check the target file
    of symlinks. This fixes some false positives with symlinks.
 
- * xbps-create(8): relative target file of symlinks aren't converted to absolute
-   anymore. This just stores what the symlink points to, does not matter if
-   it's relative or absolute path.
+ * xbps-create(8): properly detect target of relative symlinks in some cases.
 
  * libxbps: make sure that symlinks with relative target are detected and removed
    properly. Fix #78: https://github.com/voidlinux/xbps/issues/78