clang updates

The openbmc CI was recently updated to clang-12 which requires some
formatting updates to the code:
https://github.com/openbmc/openbmc-build-scripts/commit/4569bf49daaebff06be0482426908bb5497fad08

Make those updates and refresh the clang-format file with the one from
docs:
https://github.com/openbmc/docs/blob/master/style/cpp/.clang-format

Change-Id: Ieb3626526373a053ec84431e7560003f229f338d
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/phosphor-regulators/src/exception_utils.cpp b/phosphor-regulators/src/exception_utils.cpp
index 4640d0b..965deb5 100644
--- a/phosphor-regulators/src/exception_utils.cpp
+++ b/phosphor-regulators/src/exception_utils.cpp
@@ -52,8 +52,7 @@
             getExceptions(e.nested_ptr(), exceptions);
         }
         catch (...)
-        {
-        }
+        {}
 
         // Append this exception to vector
         exceptions.emplace_back(eptr);
@@ -72,8 +71,7 @@
         getMessages(inner, messages);
     }
     catch (...)
-    {
-    }
+    {}
 
     // Append error message from this exception
     messages.emplace_back(e.what());