Add support for custom decrypted TitleKey

[xprism1]

I've added the -titlekey option, so users can specify a decrypted TitleKey to use when encrypting a CIA.

[jakcron]

Thank you for your pull request! I will review it now.

[jakcron]

Thank you for your pull request, can you please address my feedback so I can merge this :)

[jakcron]

ciaset->common.titleKey will always evaluate to true because it's a defined as part of struct cia_settings:
u8 titleKey[16];

You need to respect ciaset->content.encryptCia because the common key may not be available in all target configurations (namely test).

I know content.encryptCia will be false by default unless otherwise specified in the RSF file. If you want to override this to true when specifying a title key, then I would do that in here:

cia.c

int GetSettingsFromUsrset(cia_settings *ciaset, user_settings *usrset)
{
	//...
	ciaset->content.encryptCia = usrset->common.rsfSet.Option.EnableCrypt || usrset->cia.titleKey != NULL;
	//...
}

Because a few lines later the ability to encrypt is checked, and turned off if not available. So it's safer this way.

	if(ciaset->keys->aes.commonKey[ciaset->keys->aes.currentCommonKey] == NULL && ciaset->content.encryptCia){
		fprintf(stderr,"[CIA WARNING] Common Key could not be loaded, CIA will not be encrypted\n");
		ciaset->content.encryptCia = false;
	}

[jakcron]

Can you please change the indentation from spaces to tabs to match the existing code?

[xprism1]

Addressed your feedback, and made -titlekey override content.encryptCia to true.

[jakcron]

Looks good! Thank you for your contribution :)