Add OWNERS in frameworks/compile/mclinker

* Owners are selected from top CL approvals or owners.
  They will be suggested to review/approve future CLs.
* OWNERS files are recognized by the new find-owners plugin, see .md files in
  https://gerrit.googlesource.com/plugins/find-owners/+/master/src/main/resources/Documentation/

Test: build/make/tools/checkowners.py -c -v OWNERS
Change-Id: Ifa01d7bdbcc31d084e6a487c9b21f2b29b0294e9