Switch slot of I2S

[stc1988]

This PR is fix for #1236.

Setting I2S slot to left make M5Stack cores3 to AudioOut sound.
This fix affects only esp32/m5stack_cores3.

[phoddie]

This is reasonable. Before merging, I'd like to quickly consider a slightly simpler approach. The manifest could use the ESP-IDF constant instead of a number.

    "slot": "#I2S_STD_SLOT_LEFT"

Then you can write:

	#ifndef MODDEF_AUDIOOUT_I2S_SLOT
 		#define MODDEF_AUDIOOUT_I2S_SLOT I2S_STD_SLOT_RIGHT
 	#endif

And

i2s_config.slot_cfg.slot_mask = MODDEF_AUDIOOUT_I2S_SLOT;

I think it is more clear. What do you think? (I'm OK with either approach.)

[stc1988]

Thanks for the review.
I think that is more clear too.

I have committed to this fix.

[phoddie]

Thanks for considering the proposal. Also, thank you for correctly my mistake with the "#". ;)

We'll get this merged.