If linker plugin is enabled, set non_ir_ref_regular on symbols referenced
in regular objects so that linker plugin will get the correct symbol
resolution.
bfd/
PR ld/22502
* elflink.c (_bfd_elf_merge_symbol): Also skip definition from
an IR object.
(elf_link_add_object_symbols): If linker plugin is enabled, set
non_ir_ref_regular on symbols referenced in regular objects so
that linker plugin will get the correct symbol resolution.
ld/
PR ld/22502
* testsuite/ld-plugin/lto.exp: Run PR ld/22502 test.
* testsuite/ld-plugin/pr22502a.c: New file.
* testsuite/ld-plugin/pr22502b.c: Likewise.
