[LSC] Add LOCAL_LICENSE_KINDS to system/bpf

Added SPDX-license-identifier-Apache-2.0 to:
  Android.bp
  bpfloader/Android.bp
  libbpf_android/Android.bp
  progs/Android.bp

Bug: 68860345
Bug: 151177513
Bug: 151953481

Test: m all

Exempt-From-Owner-Approval: janitorial work
Change-Id: Ia881b61da1755797085916aab5325375c82ed76e

progs/Android.bp

@@ -14,6 +14,14 @@
 // limitations under the License.
 //
 
+package {
+    // http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // the below license kinds from "system_bpf_license":
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["system_bpf_license"],
+}
+
 cc_library_headers {
     name: "bpf_prog_headers",
     export_include_dirs: ["include"],