x32 write_linux_prstatus

x32 write_linux_prstatus

x32 uses an elf_gregset64_t in the prstatus struct, which aligns the
struct to eight bytes.  This means four bytes of padding at the end of
the struct.

	* amd64-linux-tdep.c: Include elf-bfd.h.
	(amd64_x32_write_linux_prstatus): New function.
	(amd64_x32_linux_init_abi): Use it.
	* linux-tdep.c (linux_collect_regset_section_cb): Allocate an
	extra four bytes for regset buffer.
	* gdbarch.sh (elfcore_write_linux_prstatus): Remove const from info.
	* gdbarch.c: Regenerate.
	* gdbarch.h: Regenerate.