Add persistent state for Hearing Aid Profile

Defines the flag used in code and the Settings.Global key names for
persisting state of the Bluetooth Hearing Aid Profile.

Test: manual
Bug: 69623109
Change-Id: I19e68be55a80f338bdc5d39d6c3c6d251f1cb514
diff --git a/core/tests/coretests/src/android/provider/SettingsBackupTest.java b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
index 492ef72..454d209 100644
--- a/core/tests/coretests/src/android/provider/SettingsBackupTest.java
+++ b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
@@ -127,6 +127,7 @@
                     Settings.Global.BLUETOOTH_PAN_PRIORITY_PREFIX,
                     Settings.Global.BLUETOOTH_PBAP_CLIENT_PRIORITY_PREFIX,
                     Settings.Global.BLUETOOTH_SAP_PRIORITY_PREFIX,
+                    Settings.Global.BLUETOOTH_HEARING_AID_PRIORITY_PREFIX,
                     Settings.Global.BOOT_COUNT,
                     Settings.Global.CAPTIVE_PORTAL_FALLBACK_URL,
                     Settings.Global.CAPTIVE_PORTAL_HTTPS_URL,