Minijail: add kernel-style-based .clang-format file.

Based on http://clang.llvm.org/docs/ClangFormatStyleOptions.html

Running clang-format on the entire Minijail codebase suggests
a few changes, but individual code sections can use this format
just fine.

Bug: None
Change-Id: I8067b2a0e200697064a0c17c9c8042d785bea92c
1 file changed