Update git submodules

* Update external/crosvm from branch 'master'
  to 97094058235b0bc9e6f511d922c2bcd8b8dcb661
  - AARCH64 bios support
    
    Patch was slightly modified to account for the revert of commit
    f12c5ea in this branch.
    
    BUG=b:171352650
    TEST=boot test on arm cuttlefish on rockpi host with bootloader from
    https://r.android.com/1504313
    
    Change-Id: I45841178c50207ad31ce597186643a0ae1ed52ee
    
1 file changed