Vulkan: Handle forced aspect ratio changes at runtime

[stenzek]

Fixes issue 9824.

Also removes a potential hazard when changing MSAA modes on the fly.

---

This change is

[degasus]

---

Reviewed 1 of 1 files at r1.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

---

Source/Core/VideoBackends/Vulkan/Renderer.cpp, line 942 at r1 (raw file):

  bool stereo_changed = g_Config.iStereoMode != g_ActiveConfig.iStereoMode;
  bool efb_scale_changed = s_last_efb_scale != g_ActiveConfig.iEFBScale;
  bool aspect_changed = g_Config.iAspectRatio != g_ActiveConfig.iAspectRatio;

oh, using g_Config is a race condition here AFAIK. c_Config is written by the UI thread.

---

Comments from Reviewable