Fix the drifted table-position dispatch in the PowerPC pseudo filter ##arch

[phix33]

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Description

replace() applied three special cases by hardcoded ops[] position: implicit cr0 for cmp/branch, the trap TO code, and the SPR name lookup. Three .-suffixed rows (rlwimi., rlwinm., rlwnm.) were added later without bumping those numbers, so the last two guards pointed 3 rows too early:

rlwnm r3, r4, r5, 6, 7  ->  ? = rol32(r4, r5) & 0x3000000
twi 5, r3, 0            ->  if ((word) mq 5 (word) 0) trap
mfspr r3, 0x110         ->  r3 = 0x110

The rotate destination was fed through the TO decoder, twi's operand through getspr() (strtol ("r3", NULL, 16) == 0 -> SPR_MQ), and mfspr/mtspr never reached the SPR lookup at all. These now dispatch on the mnemonic, like the mask fixups already do in the same function; the stale //0..//45 comments go with them.

Two bugs found while doing that ride along as separate commits:

• rldicr took rldic's mask — !strncmp (argv[0], "rldic", 5) is tested before the rldicr arm, leaving that arm dead.
• The trap block parsed the TO code with atoi, but capstone prints TO >= 10 in hex, so switch cases 12 and 20 were unreachable. Relatedly tdu/tdui/twu/ twui are TO=31-folded 2-operand mnemonics that carried 3-operand templates.

Four tests in db/cmd/cmd_pseudo_ppc, each confirmed failing before its fix.

[trufae]

mq? twi 5, r3, 0 -> if ((word) mq 5 (word) 0) trap

also, conflicts after merging your other pr

[trufae]

these two functions can be much shorter:

// cmp* and the cr0 conditional branches: b{eq,ge,gt,le,lt,ne} with an optional +/- hint
static bool op_needs_cr0(const char *op) {
	if (r_str_startswith (op, "cmp")) {
		return true;
	}
	if (op[0] != 'b' || !op[1] || !op[2] || (op[3] && (op[4] || !strchr ("+-", op[3])))) {
		return false;
	}
	const char cond[] = { op[1], op[2], 0 };
	return strstr ("eq ge gt le lt ne", cond) != NULL;
}

// only td/tdi/tw/twi carry a TO code operand, every named form (tweq, tdlgt, tdu..) encodes it in the mnemonic
static bool op_is_trap(const char *op) {
	return !strcmp (op, "td") || !strcmp (op, "tdi") || !strcmp (op, "tw") || !strcmp (op, "twi");
}

[trufae]

also change all the strncmps with custom lentghs for just r_str_starts:

						} else if (letter == 4 && !strncmp (argv[0], "rlwimi", 6)) {

[trufae]

in other words pick this commit: dfe2c40