shill: Sort headers alphabetically (build/include_alpha)

We are going to enable build/include_alpha linter warning soon,
so in preparation for this, fixed the warnings in shill.

BUG=None
TEST=cpplint.py --filter=-build/include_order,+build/include_alpha shill/*

Change-Id: I113ed7f9dd3f465a3f660599320cdb434e7cc214
Reviewed-on: https://chromium-review.googlesource.com/209636
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/cellular_capability_universal_cdma.cc b/cellular_capability_universal_cdma.cc
index dd925f3..7b9a4bd 100644
--- a/cellular_capability_universal_cdma.cc
+++ b/cellular_capability_universal_cdma.cc
@@ -4,10 +4,10 @@
 
 #include "shill/cellular_capability_universal_cdma.h"
 
-#include <chromeos/dbus/service_constants.h>
-#include <base/strings/stringprintf.h>
 #include <base/strings/string_number_conversions.h>
 #include <base/strings/string_util.h>
+#include <base/strings/stringprintf.h>
+#include <chromeos/dbus/service_constants.h>
 
 #include "shill/cellular_bearer.h"
 #include "shill/cellular_service.h"