fix error reporting for virtual package addition

Move addition of virtual package after the dependencies have been parsed
as then the reverse dependency structers can be populated correctly.

src/add.c

@@ -116,7 +116,6 @@ static int add_main(void *ctx, struct apk_database *db, struct apk_string_array
  virtpkg->version = apk_blob_atomize(APK_BLOB_STR("0"));
  virtpkg->description = strdup("virtual meta package");
  virtpkg->arch = apk_blob_atomize(APK_BLOB_STR("noarch"));
- virtpkg = apk_db_pkg_add(db, virtpkg);
  }
 
  foreach_array_item(parg, args) {
@@ -160,6 +159,7 @@ static int add_main(void *ctx, struct apk_database *db, struct apk_string_array
  }
  }
  if (virtpkg) {
+ virtpkg = apk_db_pkg_add(db, virtpkg);
  apk_deps_add(&world, &virtdep);
  apk_solver_set_name_flags(virtdep.name,
  actx->solver_flags,