RFS: ball/1.5.0+git20220524.d85d2dd-1 [RC]

I made some changes to src:ball on top of the existing commits, fixing
the RC bugs (#1112717, #1114056), #1040385 and some other subtle
issues (no .so symlinks in -dev packages, missing dependencies).

The reprotest job timed out so the time limit should be bumped in the
project's settings.  It will fail anyway; I enumerated the remaining
issues in reproducibility.patch.

I also successfully cross-built the package on amd64 for ppc64el
(which was not possible before as it called cmake directly and didn't
pass the necessary options for cross-building).