[PPC] Fix random branch hint and update_cr0 set up.

[Rot127]

The branch hint and the update_cr0 flag can be set to true at random.

Those flags are set here:

capstone/arch/PowerPC/PPCInstPrinter.c

Lines 77 to 92 in dc69f00

	void PPC_post_printer(csh ud, cs_insn *insn, char *insn_asm, MCInst *mci)
	{
	if (((cs_struct *)ud)->detail != CS_OPT_ON)
	return;
	// check if this insn has branch hint
	if (strrchr(insn->mnemonic, '+') != NULL && !strstr(insn_asm, ".+")) {
	insn->detail->ppc.bh = PPC_BH_PLUS;
	} else if (strrchr(insn->mnemonic, '-') != NULL) {
	insn->detail->ppc.bh = PPC_BH_MINUS;
	}
	if (strrchr(insn->mnemonic, '.') != NULL) {
	insn->detail->ppc.update_cr0 = true;
	}
	}

Because the cs_insn->mnemonic gets filled after the PPC_post_printer() is called and cs_insn->mnemonic is not memset to 0 before, PPC_post_printer() tests cs_insn->mnemonic with random data.

This in turn leads randomly to incorrect setting of the branch hints and the update_cr0 flag.

The branch hints and update_cr0 flag will no longer set by checking the mnemonic once the auto-sync update is done. So this is really just a hotfix until #2013 is merged.