Build ethernet framework source into framework-connectivity-tiramisu

- move ethernet APIs, build it into framework-connectivity-tiramisu
- start ethernet service from ConnectivityServiceInitializer
- fix EthernetManager dependnecy in Tethering module
- fix EthernetNetworkSpecifier dependency in framework-connectivity
- fix the ethernet related config resource

Bug: 210586283
Test: m
Test: atest FrameworksNetTests EthernetServiceTests
Ignore-AOSP-First: Topic of Ethernet Mainline has merge conflict with
                   master, merge this CL first and cherry-pick it back.
Change-Id: I54857b8517649048a343c72797668394d5225766
diff --git a/framework/Android.bp b/framework/Android.bp
index 821879d..f31a7d5 100644
--- a/framework/Android.bp
+++ b/framework/Android.bp
@@ -86,6 +86,7 @@
         "net-utils-device-common",
     ],
     static_libs: [
+        "modules-utils-backgroundthread",
         "modules-utils-build",
         "modules-utils-preconditions",
     ],
@@ -139,6 +140,7 @@
         "//frameworks/base/tests/vcn",
         "//frameworks/libs/net/common/testutils",
         "//frameworks/libs/net/common/tests:__subpackages__",
+        "//frameworks/opt/net/ethernet/tests:__subpackages__",
         "//frameworks/opt/telephony/tests/telephonytests",
         "//packages/modules/CaptivePortalLogin/tests",
         "//packages/modules/Connectivity/Tethering/tests:__subpackages__",
@@ -212,4 +214,4 @@
         ":framework-connectivity-protos",
     ],
     output_extension: "srcjar",
-}
\ No newline at end of file
+}