Comment # 6 on bug 1205314 from Eyad Issa

Could this be caused by the swap being in a separate encrypted partition?

I opened a bug some time ago because of this and the issue was with the swap
being another partition. 

After removing the swap from fstab and crypttab the 2nd passphrase dialog was
not shown anymore.

https://bugzilla.opensuse.org/show_bug.cgi?id=1212853