Fix the disassmbly of SH instructions which have an unsigned 8-bit immediate operand.

Fix the disassmbly of SH instructions which have an unsigned 8-bit immediate operand.

	PR 22699
opcodes	* sh-opc.h (IMM0_8): Replace with IMM0_8S and IMM0_8U.  Use
	IMM0_8S for arithmetic insns and IMM0_8U for logical insns.
	* sh-dis.c (print_insn_sh): Change IMM0_8 case to IMM0_8S and add
	IMM0_8U case.

gas	* config/tc-sh.c (build_Mytes): Change operand type IMM0_8 to
	IMM0_8S and add support for IMM0_8U.
	* testsuite/gas/sh/sh4a.s: Add test of a logical insn using an
	unsigned 8-bit immediate.
	* testsuite/gas/sh/sh4a.d: Extended expected disassembly.