Always use PIC option with -shared in libtool

Libtool needs to pass PIC option -shared when creating shared object to
link regular object files with slim-lto archive.

	PR bootstrap/63784
	* libtool.m4: Add $pic_flag with -shared.

boehm-gc/

	PR bootstrap/63784
	* configure: Regenerated.

gcc/

	PR bootstrap/63784
	* configure: Regenerated.

libatomic/

	PR bootstrap/63784
	* configure: Regenerated.

libbacktrace/

	PR bootstrap/63784
	* configure: Regenerated.

libcc1/

	PR bootstrap/63784
	* configure: Regenerated.

libcilkrts/

	PR bootstrap/63784
	* configure: Regenerated.

libffi/

	PR bootstrap/63784
	* configure: Regenerated.

libgfortran/

	PR bootstrap/63784
	* configure: Regenerated.

libgomp/

	PR bootstrap/63784
	* configure: Regenerated.

libitm/

	PR bootstrap/63784
	* configure: Regenerated.

libjava/

	PR bootstrap/63784
	* configure: Regenerated.

libjava/classpath/

	PR bootstrap/63784
	* configure: Regenerated.

libobjc/

	PR bootstrap/63784
	* configure: Regenerated.

libquadmath/

	PR bootstrap/63784
	* configure: Regenerated.

libsanitizer/

	PR bootstrap/63784
	* configure: Regenerated.

libssp/

	PR bootstrap/63784
	* configure: Regenerated.

libstdc++-v3/

	PR bootstrap/63784
	* configure: Regenerated.

libvtv/

	PR bootstrap/63784
	* configure: Regenerated.

lto-plugin/

	PR bootstrap/63784
	* configure: Regenerated.

From-SVN: r217937