Close lipc handles on exit.

No idea if bad things happen if we don't, but at least this sounds more
correct. (re #696)

frontend/apps/reader/modules/readeractivityindicator.lua

@@ -45,4 +45,10 @@ function ReaderActivityIndicator:onStopActivityIndicator()
     return true
 end
 
+function ReaderActivityIndicator:coda()
+    if self.lipc_handle then
+        self.lipc_handle:close()
+    end
+end
+
 return ReaderActivityIndicator

frontend/ui/device/kindlepowerd.lua

@@ -26,7 +26,7 @@ end
 function KindlePowerD:init(model)
     local lipc = require("liblipclua")
     if lipc then
-        self.lipc_handle = lipc.init("com.github.koreader")
+        self.lipc_handle = lipc.init("com.github.koreader.kindlepowerd")
     end
 
     if model == "KindleTouch" then
@@ -83,4 +83,10 @@ function KindlePowerD:isChargingHW()
     return self.is_charging == 1
 end
 
+function KindlePowerD:coda()
+    if self.lipc_handle then
+        self.lipc_handle:close()
+    end
+end
+
 return KindlePowerD

reader.lua

@@ -30,6 +30,8 @@ local InfoMessage = require("ui/widget/infomessage")
 local UIManager = require("ui/uimanager")
 local Menu = require("ui/widget/menu")
 local Device = require("ui/device")
+local KindlePowerD = require("ui/device/kindlepowerd")
+local ReaderActivityIndicator = require("apps/reader/modules/readeractivityindicator")
 local Screen = require("ui/screen")
 local DEBUG = require("dbg")
 
@@ -42,6 +44,10 @@ function exitReader()
 
     input.closeAll()
 
+    -- Close lipc handles
+    KindlePowerD:coda()
+    ReaderActivityIndicator:coda()
+
     if not util.isEmulated() then
         if Device:isKindle3() or (Device:getModel() == "KindleDXG") then
             -- send double menu key press events to trigger screen refresh