Thanks again BigChimp, the new version works much better.
I still had some errors from the assembler like:
>> system.s:9: Error: lo register required -- `stmfd r13!,{r3,r14}'
however based on an entry in another thread I changed -Cparmv7 to -Cparmv7A and they went away.
After sorting out some library links the crosscompiler seems to work also in Lazarus.