init: Remove custom clang-format

Use a symlink to .clang-format-4 from the parent directory now that we
have it, instead of the custom .clang-format in this directory.

The changes between these files are,
Old:
ConstructorInitializerAllOnOneLineOrOnePerLine: false
TabWidth: 8
New:
ConstructorInitializerAllOnOneLineOrOnePerLine: true
TabWidth: 4

There is no reason to keep a custom .clang-format for these two
changes, and setting ConstructorInitializerAllOnOneLineOrOnePerLine to
true will be beneficial.

Test: Run clang-format and see that its output is sane
Change-Id: I5b357949eb02a60577cf57a783c0a80997b24e75