Fix Settings bug that occurs when not using JACK

[messmerd]

This fixes a regression from #7919.

Opening the settings would unconditionally try to start the JACK server if it was not already running, even if the user was using an audio backend other than JACK. When it failed to start the JACK server, it would retry a few times which made opening the Settings take several seconds. For me, it also broke my whole system's audio, requiring me to restart pipewire (see the console logs below).

This PR fixes that problem by passing the JackNoStartServer option to jack_client_open() in the setupWidget used by the Settings. AudioJack::initJackClient() continues to use the JackNullOption option, so like before, it will still attempt to start the JACK server if you select the JACK backend and restart LMMS.

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Console output showing the bug that was fixed by this PR

Click to expand

$ ./lmms 
*** WEAK-JACK: initializing
*** WEAK-JACK: OK. (0)
lilv_world_add_plugin(): warning: Duplicate plugin 
lilv_world_add_plugin(): warning: ... found in file:///home/dalton/.lv2/spectmorph.lv2/
lilv_world_add_plugin(): warning: ... and      file:///usr/local/lib/lv2/spectmorph.lv2/ (ignored)
Lv2 plugin SUMMARY: 18 of 40  loaded in 119 msecs.
For details about not loaded plugins, please set
  environment variable "LMMS_LV2_DEBUG" to nonempty.
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jackdmp 1.9.21
Copyright 2001-2005 Paul Davis and others.
Copyright 2004-2016 Grame.
Copyright 2016-2022 Filipe Coelho.
jackdmp comes with ABSOLUTELY NO WARRANTY
This is free software, and you are welcome to redistribute it
under certain conditions; see the file COPYING for details
no message buffer overruns
no message buffer overruns
no message buffer overruns
JACK server starting in realtime mode with priority 10
self-connect-mode is "Don't restrict self connect requests"
audio_reservation_init
Acquire audio card Audio0
creating alsa driver ... hw:0|hw:0|1024|2|48000|0|0|nomon|swmeter|-|32bit
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
ATTENTION: The playback device "hw:0" is already in use. The following applications  are using your soundcard(s) so you should  check them and stop them as necessary before  trying to start JACK again:
pipewire (process ID 2501)
JackTemporaryException : now quits...

Released audio card Audio0

audio_reservation_finish

Cannot initialize driver

JackServer::Open failed with -1

Failed to open server

Cannot connect to server socket err = No such file or directory

Cannot connect to server request channel

Cannot connect to server socket err = No such file or directory

Cannot connect to server request channel

jack server is not running or cannot be started

JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock

JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock

jack_client_open() failed, Status: 0x11

Overall operation failed. JACK dependencies might need to be installed.

Could not connect to JACK server.