Preliminary support for generating shared libraries, from Eric

	Preliminary support for generating shared libraries, from Eric
	Youngdale <ericy@cais.cais.com>.
	* elfcode.h (prep_headers): If DYNAMIC, set e_type to ET_DYN.
	(elf_link_add_object_symbols): If generating a shared library,
	create dynamic sections for first input BFD with the right format.
	(elf_link_create_dynamic_sections): Don't create .interp section
	if creating a shared library.
	(elf_link_input_bfd): Skip dynamic sections in input file.
	(elf_bfd_final_link): If creating a shared library, it's OK for
	dynobj to have sections which are not SEC_IN_MEMORY.
	* elf32-i386.c (elf_i386_size_dynamic_sections): Only set .interp
	section if not creating a shared library.
	* elf32-sparc.c (elf_sparc_size_dynamic_sections): Likewise.