x86: Count PLT for GOTOFF relocation against IFUNC symbol

x86: Count PLT for GOTOFF relocation against IFUNC symbol

Since GOTOFF relocations against IFUNC symbols must go through PLT,
set PLT reference count to 1 for GOTOFF relocation.

bfd/

	PR ld/27998
	* elfxx-x86.c (elf_x86_allocate_dynrelocs): Count PLT for GOTOFF
	relocation against IFUNC symbols.
	(_bfd_x86_elf_adjust_dynamic_symbol): Likewise.

ld/

	PR ld/27998
	* testsuite/ld-i386/i386.exp: Run PR ld/27998 tests.
	* testsuite/ld-i386/pr27998a.d: New file.
	* testsuite/ld-i386/pr27998a.s: Likewise.
	* testsuite/ld-i386/pr27998b.d: Likewise.
	* testsuite/ld-i386/pr27998b.s: Likewise.