LTO: Properly check wrapper symbol

LTO: Properly check wrapper symbol

Add wrapper_symbol to bfd_link_hash_entry and set it to true for wrapper
symbol. Set wrap_status to wrapper if wrapper_symbol is true in LTO.

Note: Calling unwrap_hash_lookup to check for the wrapper symbol works
only when there is a definition for the wrapped symbol since references
to the wrapped symbol have been redirected to the wrapper symbol.

bfd/

	PR ld/31956
	* linker.c (bfd_wrapped_link_hash_lookup): Set wrapper_symbol
	for wrapper symbol.

include/

	PR ld/31956
	* bfdlink.h (bfd_link_hash_entry): Add wrapper_symbol.

ld/

	PR ld/31956
	* plugin.c (get_symbols): Set wrap_status to wrapper if
	wrapper_symbol is set.
	* testsuite/ld-plugin/lto.exp: Run PR ld/31956 tests.
	* testsuite/ld-plugin/pr31956a.c: New file.
	* testsuite/ld-plugin/pr31956b.c: Likewise.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>