Currently, initramfs-tools-core has in its Recommends line:

 Recommends: busybox | busybox-static

The busybox-static alternative is not needed, since busybox-static package
already has Provides: busybox, and will satisfy first alternative.

However, we're making changes in busybox-static package (see #1147074)
which will make it incompatible with initramfs-tools usage of it.

Please drop busybox-static alternative from Recommends to allow us to
proceed.  This is a trivial change.

Thanks,

/mjt