ubsan: hppa: left shift of negative value

ubsan: hppa: left shift of negative value

bfd/
	* libhppa.h (hppa_field_adjust, bfd_hppa_insn2fmt): Delete forward
	declaration.  Move ATTRIBUTE_UNUSED to definition.
	(sign_extend, low_sign_extend, sign_unext, low_sign_unext),
	(re_assemble_3, re_assemble_12, re_assemble_14, re_assemble_16),
	(re_assemble_17, re_assemble_21, re_assemble_22): Likewise.  Make
	args and return value unsigned.  Use unsigned variables.
	(hppa_rebuild_insn): Similarly.
opcodes/
	* hppa-dis.c (extract_16, extract_21, print_insn_hppa): Use
	unsigned variables.