[BZ #737]
* sysdeps/i386/Makefile (defines): If -mno-tls-direct-seg-refs appears
in $(CFLAGS), add -DNO_TLS_DIRECT_SEG_REFS.
* sysdeps/unix/sysv/linux/i386/sysdep.h [USE___THREAD]
(SYSCALL_ERROR_HANDLER) [NO_TLS_DIRECT_SEG_REFS]: Load thread pointer
from %gs:0 and add to that value, rather that direct %gs:OFFSET access.
* sysdeps/unix/i386/sysdep.S [NO_TLS_DIRECT_SEG_REFS]: Likewise.