Work around lack of dlpi_tls_modid before Solaris 11.5

Work around lack of dlpi_tls_modid before Solaris 11.5

2019-04-14  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
	    Iain Buclaw  <ibuclaw@gdcproject.org>

	PR d/88150
	* m4/druntime/os.m4 (DRUNTIME_OS_DLPI_TLS_MODID): New macro.
	* configure.ac: Use it.
	Call AC_USE_SYSTEM_EXTENSIONS.
	* configure: Regenerate.
	* Makefile.in, libdruntime/Makefile.in, src/Makefile.in,
	testsuite/Makefile.in: Regenerate.
	* libdruntime/gcc/config.d.in (OS_Have_Dlpi_Tls_Modid): Define.
	* libdruntime/gcc/sections/elf_shared.d: Import gcc.config.
	(scanSegments) <PT_TLS> [OS_Have_Dlpi_Tls_Modid]: Use
	dlpi_tls_modid.
	[Solaris]: Use dlinfo(RTLD_DI_LINKMAP) to get rt_tlsmodid.
	Otherwise clear pdso._tlsMod, pdso._tlsSize.
	(getTLSRange) [Solaris && !OS_Have_Dlpi_Tls_Modid]: Readjust mod.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@270347 138bc75d-0d04-0410-961f-82ee72b054a4