hikey-kernel: Update kernel prebuilt with USB audio support (664e6d0) am: 8c0343c2a8 am: ce2f2599b1 am: 3680feb8ab
am: ec58b5976d

* commit 'ec58b5976ddcb537041f0087f68ed7b6f9935da8':
  hikey-kernel: Update kernel prebuilt with USB audio support (664e6d0)

Change-Id: Ia1af1e53c1c0a9beb22e332e978f937446a7d6f1