Pass host specific ABI opts from mkoffload.

The patch adds an option -foffload-abi-host-opts, which
is set by host in TARGET_OFFLOAD_OPTIONS, and mkoffload then passes its value
to host_compiler.

gcc/ChangeLog:
	PR target/96265
	* common.opt (foffload-abi-host-opts): New option.
	* config/aarch64/aarch64.cc (aarch64_offload_options): Pass
	-foffload-abi-host-opts.
	* config/i386/i386-options.cc (ix86_offload_options): Likewise.
	* config/rs6000/rs6000.cc (rs6000_offload_options): Likewise.
	* config/nvptx/mkoffload.cc (offload_abi_host_opts): Define.
	(compile_native): Append offload_abi_host_opts to argv_obstack.
	(main): Handle option -foffload-abi-host-opts.
	* config/gcn/mkoffload.cc (offload_abi_host_opts): Define.
	(compile_native): Append offload_abi_host_opts to argv_obstack.
	(main): Handle option -foffload-abi-host-opts.
	* lto-wrapper.cc (merge_and_complain): Handle
	-foffload-abi-host-opts.
	(append_compiler_options): Likewise.
	* opts.cc (common_handle_option): Likewise.

Signed-off-by: Prathamesh Kulkarni <prathameshk@nvidia.com>