keystore2: link to android.security flags library

Make it possible for keystore2 to check android.security flags.

Bug: 296464083
Test: Build
Change-Id: I263945093ed9c76d914018b7ae24bf6151157c0c
diff --git a/keystore2/Android.bp b/keystore2/Android.bp
index 271f94d..2e6eb17 100644
--- a/keystore2/Android.bp
+++ b/keystore2/Android.bp
@@ -42,6 +42,7 @@
         "android.security.metrics-rust",
         "android.security.rkp_aidl-rust",
         "libaconfig_android_hardware_biometrics_rust",
+        "libandroid_security_flags_rust",
         "libanyhow",
         "libbinder_rs",
         "libkeystore2_aaid-rust",