Remove non-ascii & unprintable characters

These non-ascii & unprintable characters aren't needed.

Change-Id: I129f729f66d6a692de729d76971f7deb7a19c254
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/15977
Tested-by: build bot (Jenkins)
Reviewed-by: Omar Pakker
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/ec/quanta/ene_kb3940q/acpi/battery.asl

@@ -67,7 +67,7 @@ Device (BATX)
 		Store (Zero, BFWK)
 	}
 
-	// Device insertion/removal control method that returns a device’s status.
+	// Device insertion/removal control method that returns a device's status.
 	// Power resource object that evaluates to the current on or off state of
 	// the Power Resource.
 	Method (_STA, 0, Serialized)