PEi386/COFF: handle relocation overflows, i.e., if a section is
marked with the flag (MY)IMAGE_SCN_LNK_NRELOC_OVFL, then
the first entry in the relocation table holds the 32-bit
relocation count rather than 16-bit number in the section header.
Apparently, a version of the MS PE spec exists that spells this
out, but haven't been able to locate it (perhaps people on the
'inside' could try to locate an up-to-date version...?) winnt.h
is clear enough about it though (as is the GNU libbfd sources).

This is the Right Way to compute the relocation count, but
unfortunately libbfd / GNU ld is generating bogus output
when the reloc field overflows (causing objdump/nm etc. to
crash when trying to read the generated output!) Looking into it.

Once this has been cleared up/fixed, the splitting up of HSstd.o
(and HSwin32.o) should be a thing of the past. I've taken the
liberty of disabling the suspiciously-large-reloc-section test
already.