remove BPF_CONTINUE and BPF_DELETED constants

These are apparently not used anywhere, and this can be trivially
confirmed via code search.

Test: builds
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I738c83c1b00bf9a7d7344a4b31bf80581788ec10
diff --git a/libbpf_android/include/bpf/BpfUtils.h b/libbpf_android/include/bpf/BpfUtils.h
index 23026bb..376b726 100644
--- a/libbpf_android/include/bpf/BpfUtils.h
+++ b/libbpf_android/include/bpf/BpfUtils.h
@@ -177,9 +177,6 @@
         if (android::bpf::getBpfSupportLevel() != android::bpf::BpfLevel::NONE) return; \
     } while (0)
 
-constexpr int BPF_CONTINUE = 0;
-constexpr int BPF_DELETED = 1;
-
 bool operator==(const StatsValue& lhs, const StatsValue& rhs);
 bool operator==(const UidTag& lhs, const UidTag& rhs);
 bool operator==(const StatsKey& lhs, const StatsKey& rhs);