Fix internal error when applying TLSDESC relocations with no TLS segment.

Fix internal error when applying TLSDESC relocations with no TLS segment.

gold/
	PR gold/19353
	* aarch64.cc (Target_aarch64::relocate_tls): Don't insist that
	we have a TLS segment for GD-to-IE optimization.
	* i386.cc (Target_i386::tls_gd_to_ie): Remove tls_segment parameter.
	Adjust all calls.
	(Target_i386::tls_desc_gd_to_ie): Likewise.
	(Target_i386::relocate_tls): Don't insist that we have a TLS segment
	for TLSDESC GD-to-IE optimizations.
	* x86_64.cc (Target_x86_64::tls_gd_to_ie): Remove tls_segment parameter.
	Adjust all calls.
	(Target_x86_64::tls_desc_gd_to_ie): Likewise.
	(Target_x86_64::relocate_tls): Don't insist that we have a TLS segment
	for TLSDESC GD-to-IE optimizations.