[fpc-pascal]parameter is 0x0 on callback

[Peter Vreman]

> Here it is (as attachment, hopefully the list processor doesn't strip it
> off):

1.9.4 reports:

main192.pp(25,52) Error: Incompatible type for arg no. 1: Got "<address of
procedure(TCustomer);CDecl>", expected "<procedure variable type of
procedure(TCustomer);Register>"