Use always non GL VU-Meters in case no sufficiant GL version is available

[daschuer]

This fixes #11286 a regression since #10893

[JoergAtGithub]

I tested this /w and /wo --safemode for 2.3 branch and this PR. The test showed, that this VU-Meter is broken for --safemode in 2.3 branch, but not for this PR.

I noticed the following unrelated issue: If I use --safemode, OpenGL waveforms are disabled and only the non-OpenGL waveforms are listed in the preferences, as supposed to be. But none of these non-OpenGL waveforms are rendered in Safemode, if I select them, I see just a black area.
If I start Mixxx without --safemode option and select a non-OpenGL waveform, the waveforms are working.

[JoergAtGithub]

Code LGTM

[Swiftb0y]

typo which results in different semantics... Would probably have been caught by -Wconversion

Suggested change

	if (!CmdlineArgs::Instance().getUseVuMeterGL() |
	(!pWaveformWidgetFactory->isOpenGlAvailable() &&
	if (!CmdlineArgs::Instance().getUseVuMeterGL() ||
	(!pWaveformWidgetFactory->isOpenGlAvailable() &&

[JoergAtGithub]

I will create a PR to fix this!

[Swiftb0y]

Thank you.

[JoergAtGithub]

Here it is: #11292