x86: Report expected register for elf_x86_tls_error_indirect_call

Since R_386_TLS_DESC_CALL can only be used with

	call	*variable@TLSCALL(%eax)

and R_X86_64_TLSDESC_CALL can only be used with

	call	*variable@TLSCALL(%rax)

update TLS transition error report to display the expected register in
indirect CALL.

bfd/

	PR ld/32017
	* elfxx-x86.c (_bfd_x86_elf_link_hash_table_create): Initialize
	the ax_register field.
	(_bfd_x86_elf_link_report_tls_transition_error): Report the
	expected register in elf_x86_tls_error_indirect_call error.
	* elfxx-x86.h (elf_x86_link_hash_table): Add ax_register.

ld/

	PR ld/32017
	* testsuite/ld-i386/tlsgdesc2.d: Updated.
	* testsuite/ld-i386/tlsgdesc2.s: Change jmp to call via ECX.
	* testsuite/ld-x86-64/tlsdesc4.d: Updated.
	* testsuite/ld-x86-64/tlsdesc4.s: Change jmp to call via RCX.

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