Add a note for an AVX2 check

bucket/mpv-git.json

@@ -5,6 +5,8 @@
     "license": "LGPL-2.1-or-later,GPL-2.0-or-later",
     "notes": [
         "This is a x86-64-v3 build, if your CPU was made before 2013 (x86-64-v2 or earlier), use versions/mpv-git-v1",
+        "To check applicability of your CPU, run the following in PowerShell:",
+        "(Add-Type -MemberDefinition '[DllImport(\"kernel32.dll\")] public static extern bool IsProcessorFeaturePresent(int ProcessorFeature);' -Name 'Kernel32'-Namespace 'Win32'-PassThru)::IsProcessorFeaturePresent(40)",
         "To set and unset file type associations and AutoPlay handlers, run '$dir\\installer\\mpv-install.bat' and '$dir\\installer\\mpv-uninstall.bat' as administrator, respectively.",
         "You can use Icaros ('nonportable/icaros-np') to enable thumbnails for all media types."
     ],