Input: Minor comment tweaks (#9441)

frontend/device/input.lua

@@ -225,7 +225,7 @@ end
 
 function Input:init()
     -- Initialize instance-specific tables
-    -- NOTE: Both of these arrays may be destroyed & recreated at runtime, so we don't want a parent/class object for those.
+    -- NOTE: All of these arrays may be destroyed & recreated at runtime, so we don't want a parent/class object for those.
     self.timer_callbacks = {}
     self.MTSlots = {}
     self.active_slots = {}

frontend/device/kindle/device.lua

@@ -989,7 +989,10 @@ function KindleBasic3:init()
 
     Kindle.init(self)
 
-    self.input.snow_protocol = true -- cf. https://github.com/koreader/koreader/issues/5070
+    -- This device doesn't emit ABS_MT_TRACKING_ID:-1 events on contact lift,
+    -- so we have to rely on contact lift detection via BTN_TOUCH:0,
+    -- c.f., https://github.com/koreader/koreader/issues/5070
+    self.input.snow_protocol = true
     self.input.open(self.touch_dev)
     self.input.open("fake_events")
 end