Reload --as-needed libraries inside groups

Reload --as-needed libraries inside groups

When a shared library appears within --start-group/--end-group ld may
only discover a need for loading the library on the second or
subsequent pass over archive libraries, as more objects are extracted.

ld/
	PR 17068
	* ldlang.c (load_symbols): Always check flags.reload.
	(open_input_bfds): Always reload --as-needed shared libraries,
	not just when rescanning.
	* ldlang.h (struct lang_input_statement_flags): Update reload comment.
	* plugin.c (plugin_should_reload): Assume shared library arg.
	* plugin.h (plugin_should_reload): Update comment.
ld/testsuite
	* ld-elf/pr17068.s: New.
	* ld-elf/pr17068a.s: New.
	* ld-elf/pr17068b.s: New.
	* ld-elf/pr17068c.s: New.
	* ld-elf/pr17068d.s: New.
	* ld-elf/pr17068e.s: New.
	* ld-elf/pr17068ez.s: New.
	* ld-elf/elf.exp: Run new test.