[xb] Remove useless version check

The version is already checked in xenia-build.
Add an actually useful 64-bit check.

xb.ps1

@@ -1,27 +1,15 @@
-function Write-FatalError($message) {
-    [Console]::ForegroundColor = 'red'
-    [Console]::Error.WriteLine($message)
-    [Console]::ResetColor()
-    Exit 1
-}
-
-$pythonExecutables = 'python', 'python3'
+$pythonExecutables = "python", "python3", "py"
 foreach ($pythonExecutable in $pythonExecutables) {
     if (!$pythonPath) {
         $pythonPath = powershell -NoLogo -NonInteractive "(Get-Command -ErrorAction SilentlyContinue $pythonexecutable).Definition" # Hack to not give command suggestion
-    } else {
-        break
+        if ($pythonPath) {
+            break
+        }
     }
 }
 # Neither found, error and exit
-$pythonMinimumVer = 3,9
 if (!$pythonPath) {
-    Write-FatalError "ERROR: Python $($pythonMinimumVer[0]).$($pythonMinimumVer[1])+ must be installed and on PATH:`nhttps://www.python.org/"
-}
-
-& $pythonPath -c "import sys; sys.exit(1 if not sys.version_info[:2] >= ($($pythonMinimumVer[0]), $($pythonMinimumVer[1])) else 0)"
-if ($LASTEXITCODE -gt 0) {
-    Write-FatalError "ERROR: Python version mismatch, not at least $($pythonMinimumVer[0]).$($pythonMinimumVer[1]).`nFound Python executable was `"$($pythonPath)`"."
+    Throw "ERROR: Python 3.9+ 64-bit must be installed and on PATH:`nhttps://www.python.org/"
 }
 
 & $pythonPath "$($PSScriptRoot)/xenia-build" $args