Reduce the cases where TLS fixups are changed to LE.

Change TLS fixup type to Local Exec in a reduced numbed of cases.  Add
some additional support for handling GD and IE fixups.

ChangeLog:

        * config/arc/arc.c (arc_print_operand): Handle global dynamic,
	UNSPEC_TLS_GD, fixups.
	(arc_print_operand_address): Handle Imediate Exec, UNSPEC_TLS_IE,
	fixups.
	(arc_legitimize_tls_address): Change Local Dynamic to Local Exec
	when we're not compiling PIC code.