Update git submodules

* Update external/dtc from branch 'master'
  to 3c9bd3b5789d0df7f5b76ccc1dfa8a8ab4eabecc
  - Remove hridya@ from OWNERS file
    
    Test: N/A
    Bug: N/A
    Change-Id: Icbcb60ef40259b0b8ef700bbe6c6fc7cca83236a
    
1 file changed