Fix PlatformIO intellisense (#1616)

The `_idedata` has been changed to `__idedata` in newer PlatformIO core versions per https://github.com/platformio/platformio-core/commit/158aabbdf23ed1ff8f5e3f01fb4ef1723a78d3bb. This change has broken the logic to expand out the `-iprefix PATH @INCLUDEFILE` argument into its individual include paths, causing Intellisense breakages on some VSCode systems and other IDEs that didn't handle these arguments correctly or in which the path was corrupted.

tools/platformio-build.py

@@ -53,7 +53,7 @@ for l in file_lines:
 
 def is_pio_build():
 	from SCons.Script import COMMAND_LINE_TARGETS
-	return "idedata" not in COMMAND_LINE_TARGETS and "_idedata" not in COMMAND_LINE_TARGETS
+	return all([x not in COMMAND_LINE_TARGETS for x in ["idedata", "_idedata", "__idedata"]])
 
 # get all activated macros
 flatten_cppdefines = env.Flatten(env['CPPDEFINES'])