Midi task should not be pinned if AMY_MIDI_IS_NONE

[fesch]

I noticed, that the midi task is being pinned (midi.c:374) even if AMY_MIDI_IS_NONE is chosen as midi config. If in Arduino the Serial (UART_NUM_1) is used too, which will probably mostly be the the case, the processor crashes:

21:37:53.748 -> Starting ...
21:37:53.748 -> E (176) uart: UART driver already installed
21:37:53.748 -> ESP_ERROR_CHECK failed: esp_err_t 0xffffffff (ESP_FAIL) at 0x400089e2
21:37:53.793 -> file: "c:\Users\xyz\Arduino\Arduino IDE\libraries\amy\src\midi.c" line 347
21:37:53.793 -> func: run_midi_task
21:37:53.793 -> expression: uart_driver_install(uart_num, uart_buffer_size, 0, 0, NULL, 0)
21:37:53.793 -> 
21:37:53.824 -> abort() was called at PC 0x4ff06ca1 on core 0

I suggest two things:

• Not to pin the midi task in case AMY_MIDI_IS_NONE
• Give the user the possibility to chose anther UART as the default one, e.g. introducing something like "int amy_config.midi_uart" or similar.

[bwhitman]

Good catch!!

[bwhitman]

We just fixed this up -- there's a new midi_uart flag in config, and also the midi uart code will not run if AMY_MIDI_IS_UART is not set. Thanks!