ec: Add directory local configuration for Emacs
ec: Add directory local configuration for Emacs

Since ec uses Linux kernel code style, this adds support for a feature
in emacs to use a specific code style in a directory and its
subdiretories. Looks like this technique is used in a few other spots in
chromium code.

BUG=None
BRANCH=none
TEST=Emacs 26.1 recognizes and uses just fine

Change-Id: Ic8007accf6746cb1a4c2ca0050fa06884d598da3
Signed-off-by: Jack Rosenthal <d3f605bef1867f59845d4ce6e4f83b8dc9e4e0ae@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1493036
Commit-Ready: ChromeOS CL Exonerator Bot <fa429e5907f00867f797423aea74327bb02c91b6@appspot.gserviceaccount.com>
Reviewed-by: Tim Wawrzynczak <86444811eee8c2cb29e29a251d7a069e64ccc665@chromium.org>
Reviewed-by: Raul E Rangel <9a9c998e11a2655b1de9a05eeeef5f710c0dc7ed@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec