Like on libthr, there is an i386_set_gsbase() stub implementation here
to avoid libc.so.5 issues. This should likely be a weak symbol and I
expect this will be fixed soon.
Approved by: re
can't use the i386_set_ldt() family of routines, because they are not
implemented. Instead, use the recently exposed direct access sysarch
routines for setting what %fs and %gs point to.
Use this for the i386 TLS _set_tp() routine, but only when compiling to
run as a 32 bit support binary for amd64 kernels.