RISC-V: Pretty print values formed with lui and addiw.

RISC-V: Pretty print values formed with lui and addiw.

The disassembler has support to pretty print values created by an lui/addi
pair, but there is no support for addiw.  There is also no support for
c.addi and c.addiw.  This patch extends the pretty printing support to
handle these 3 instructions in addition to addi.  Existing testcases serve
as tests for the new feature.

	opcodes/
	* riscv-dis.c (maybe_print_address): New arg wide.  Sign extend when
	wide is true.
	(print_insn_args): Fix calls to maybe_print_address.  Add checks for
	c.addi, c.addiw, and addiw, and call maybe_print_address for them.

	gas/
	* testsuite/gas/riscv/insn.d: Update for disassembler change.
	* testsuite/gas/li32.d, testsuite/gas/li64.d: Likwise.
	* testsuite/gas/lla64.d: Likewise.