Fix a small set of Z80 problems.

Fix a small set of Z80 problems.

	PR 25641
	PR 25668
	PR 25633
gas	Fix disassembling ED+A4/AC/B4/BC opcodes.
	Fix assembling lines containing colonless label and instruction
	with first operand inside parentheses.
	Fix registration of unsupported by target CPU registers.
	* config/tc-z80.c: See above.
	* config/tc-z80.h: See above.
	* testsuite/gas/z80/colonless.d: Update test.
	* testsuite/gas/z80/colonless.s: Likewise.
	* testsuite/gas/z80/ez80_adl_all.d: Likewise.
	* testsuite/gas/z80/ez80_unsup_regs.d: Likewise.
	* testsuite/gas/z80/ez80_z80_all.d: Likewise.
	* testsuite/gas/z80/gbz80_unsup_regs.d: Likewise.
	* testsuite/gas/z80/r800_unsup_regs.d: Likewise.
	* testsuite/gas/z80/unsup_regs.s: Likewise.
	* testsuite/gas/z80/z180_unsup_regs.d: Likewise.
	* testsuite/gas/z80/z80.exp: Likewise.
	* testsuite/gas/z80/z80_strict_unsup_regs.d: Likewise.
	* testsuite/gas/z80/z80_unsup_regs.d: Likewise.
	* testsuite/gas/z80/z80n_unsup_regs.d: Likewise.

opcodes	* z80-dis.c: Fix disassembling ED+A4/AC/B4/BC opcodes.