shill: wimax: Refactor service management out of WiMax into WiMaxProvider.

This allows WiMAX service management to be independent from the
availability of WiMAX devices.

BUG=chrome-os-partner:9907
TEST=unit tests

Change-Id: I52ad31ed8ef1d271b04bbd2cfc17729a5c112831
Reviewed-on: https://gerrit.chromium.org/gerrit/23511
Commit-Ready: Darin Petkov <petkov@chromium.org>
Reviewed-by: Darin Petkov <petkov@chromium.org>
Tested-by: Darin Petkov <petkov@chromium.org>
diff --git a/mock_wimax_provider.cc b/mock_wimax_provider.cc
index 8053be1..c5d0dd7 100644
--- a/mock_wimax_provider.cc
+++ b/mock_wimax_provider.cc
@@ -4,6 +4,8 @@
 
 #include "shill/mock_wimax_provider.h"
 
+#include "shill/wimax.h"
+
 namespace shill {
 
 MockWiMaxProvider::MockWiMaxProvider()