This was discussed in bug 1216971

Partition configuration:

https://documentation.suse.com/sles/15-SP5/html/SLES-all/cha-configuration-installation-options.html#ay-partition-configuration

The "partition_type" section reads:

> Optional. Allowed values are primary (default) and logical.When using an msdos partition table, this element sets the type of the partition. The value can be primary or logical. This value is ignored when using a gpt partition table, because such a distinction does not exist in that case.

But the only valid value is "primary". Any other value generates an XML validation error.
When there are 5 or more partitions in a msdos partition table, some will have to be logical. Up to 3 partitions can be manually specified as primary by creating the partition_type tag with a value of primary.

There's also another issue with our documentation regarding the same feature here:

> https://documentation.suse.com/sles/15-SP5/single-html/SLES-autoyast/#sec-ay-12vs15-partitioning-forcing-primary
> It is still possible to force a partition as primary (only on MS-DOS partition tables) by setting the primary_type to primary. However, any other value, like logical, will be ignored by AutoYaST, which will automatically determine the partition type.

There is no primary_type tag as described in the documentation. That section is actually talking about the partition_type tag.
However, values other than primary are not ignored as stated in the documentation. They actually generate XML validation errors.

This has been the behavior since at least SLES 15 (all service packs), so it should probably be updated in the documentation for each service pack.

Let me know if anything further is needed.

Thanks!