Enforce git commit message rules

CI recently has added a feature for enforcing git commit message rules.
For the moment, this is optional and opt-in per repo.  Enable it for
OpenBMC.

Tested:
CI only.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I9cfe426bbcfd3f8fec34e2f92d29c03631eaee32
diff --git a/.openbmc-enforce-gitlint b/.openbmc-enforce-gitlint
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/.openbmc-enforce-gitlint