Preset dropdown menu is not disabled when LE audio is toggled off

Root Cause: Preset spinner should update visibility at the right time.

Solution: Check if HapClientProfile is connected when active device
changed and when preset spinner is created.

Bug: 347629387
Test: atest HearingDevicesDialogDelegateTest
Flag: EXEMPT bugfix
Change-Id: Ic3becf2185a8bb26f5c3c3bbf737959fe5019b20