Remove mention of running ninja directly

[reftel]

It may be true that if one uses a Meson version that is more than 4 years old, one might need to run ninja directly, but details like that should be safe to keep out of the simple getting started guide.

[eli-schwartz]

Actually I strongly disagree and think that ninja should always be used specifically, no matter how new meson is, except specifically when using MSVC due to this bug: ninja-build/ninja#1610

meson compile is badly designed and cannot be fixed without breaking existing users. I've had to roll back its usage elsewhere in order to re-enable fundamental features of ninja-based workflows that were broken by using meson compile.

But I appear to be in the minority about thinking this...

[dcbaker]

I agree with @eli-schwartz, I wish I'd never written meson compile. I had hoped for something that could be used in cases where compatibility between backends was more important than feature richness, like in CI's where people basically wanted build, use X cores, test. the whole point was to avoid:

if windows:
   msbuild /MP:8 ...
else:
  ninja -j8 ...