Although the OS is still not listed in PAM, I believe it's only a matter of time before it's updated.
You can find the product and documentation of SLES 12 for SAP here:
https://www.suse.com/documentation/sles_for_sap/pdfdoc/sles_for_sap_guide/sles_for_sap_guide.pdf
It's not currently supported to have BI 4.1 SPS05 running on SLES 12, though.