[LSC] Add LOCAL_LICENSE_KINDS to build/soong

Added SPDX-license-identifier-Apache-2.0 to:
  java/core-libraries/Android.bp
  mk2rbc/Android.bp

Bug: 68860345
Bug: 151177513
Bug: 151953481

Test: m all

Exempt-From-Owner-Approval: janitorial work
Change-Id: Iaf8546fc945b04b71cd5cb1c7c16a9e15f608d02

mk2rbc/Android.bp

@@ -13,6 +13,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
 blueprint_go_binary {
     name: "mk2rbc",
     srcs: ["cmd/mk2rbc.go"],