Update git submodules

* Update trusty/user/app/sample from branch 'master'
  to a1c3f20e381c5dc5de286c756954a3d79b207a10
  - [skel_rust] Add print using trusty-std
    
    Adds a use of the trusty-std crate to test that it is built and can
    print to stdout.
    
    Test: build.py && run, check for print in logs
    Bug: 193278128
    Change-Id: I300d908fa16f7989021125ed95357031cb1c06eb
    

* Update trusty/user/base from branch 'master'
  to 128c84212b119f4f5acad24596966961baa97981
  - [trusty-std] Add fallible vector push
    
    Adds a a fallible push method to Vec.
    
    Test: build.py
    Bug: 193278128
    Change-Id: Iac68b17cee9ffcd456996d0e56b6cadfa4361784
    
  - [rust] Add an initial Rust standard lib for Trusty
    
    Adds a Trusty standard library crate containing minimal APIs applicable
    to Trusty, extracted from the upstream standard library.
    
    Includes a memory allocator, CStr and CString, and basic unbuffered
    standard output.
    
    Test: build.py
    Bug: 193278128
    Change-Id: Ifded72ca8e2da310371cb7fe060b8bcd204f2978
    
2 files changed