* tc-hppa.c: Add %dp and %rp as synonyms for %r27 and %r2 in the

	* tc-hppa.c: Add %dp and %rp as synonyms for %r27 and %r2 in the
	predefined register table.
	(pa_parse_number): Handle %rp in common register shortcut code.
	Consistently set return value to -1 for an error.  Clean up error
	messages and only print them when "print_errors" is true.  Handle
	empty string case like the HP assembler -- assume a value of
	zero.