Implement ASM_DECLARE_FUNCTION_NAME using ASM_OUTPUT_FUNCTION_LABEL

Implement ASM_DECLARE_FUNCTION_NAME using ASM_OUTPUT_FUNCTION_LABEL

gccint recommends using ASM_OUTPUT_FUNCTION_LABEL in
ASM_DECLARE_FUNCTION_NAME, but many implementations use
ASM_OUTPUT_LABEL instead.  It's inconsistent and prevents changes to
ASM_OUTPUT_FUNCTION_LABEL from affecting the respective targets.

Link: https://inbox.sourceware.org/gcc-patches/20240102194511.3171559-2-iii@linux.ibm.com/
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
gcc/ChangeLog:

	* config/aarch64/aarch64.cc (aarch64_declare_function_name):
	Use ASM_OUTPUT_FUNCTION_LABEL ().
	* config/alpha/alpha.cc (alpha_start_function): Likewise.
	* config/arm/aout.h (ASM_DECLARE_FUNCTION_NAME): Likewise.
	* config/arm/arm.cc (arm_asm_declare_function_name): Likewise.
	* config/bfin/bfin.h (ASM_DECLARE_FUNCTION_NAME): Likewise.
	* config/c6x/c6x.h (ASM_DECLARE_FUNCTION_NAME): Likewise.
	* config/gcn/gcn.cc (gcn_hsa_declare_function_name): Likewise.
	* config/h8300/h8300.h (ASM_DECLARE_FUNCTION_NAME): Likewise.
	* config/ia64/ia64.cc (ia64_start_function): Likewise.
	* config/mcore/mcore-elf.h (ASM_DECLARE_FUNCTION_NAME):
	Likewise.
	* config/microblaze/microblaze.cc (microblaze_function_prologue):
	Likewise.
	* config/mips/mips.cc (mips_start_unique_function): Return the
	tree.
	(mips_start_function_definition): Use
	ASM_OUTPUT_FUNCTION_LABEL ().
	(mips_finish_stub): Pass the tree to
	mips_start_function_definition ().
	(mips16_build_function_stub): Likewise.
	(mips16_build_call_stub): Likewise.
	(mips_output_function_prologue): Likewise.
	* config/pa/pa.cc (pa_output_function_label): Use
	ASM_OUTPUT_FUNCTION_LABEL ().
	* config/riscv/riscv.cc (riscv_declare_function_name): Likewise.
	* config/rs6000/rs6000.cc (rs6000_elf_declare_function_name):
	Likewise.
	(rs6000_xcoff_declare_function_name): Likewise.