.clang-format: add more style options

These options direct the formatter to enforce style which is closer to
the EC codebase status quo:

  - no single line functions
  - avoid function return type on a separate line

BRANCH=none
BUG=none
TEST=ran clang-format and observed desired behavior

Change-Id: I62012f58483f11c46925f2c6c4c6fff72b9e90f8
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1496204
Reviewed-by: Raul E Rangel <rrangel@chromium.org>

.clang-format

@@ -1,4 +1,5 @@
 Language:                                  Cpp
+AllowShortFunctionsOnASingleLine:          None
 AllowShortIfStatementsOnASingleLine:       false
 BasedOnStyle:                              LLVM
 BreakBeforeBraces:                         Linux
@@ -6,5 +7,6 @@ ColumnLimit:                               80
 ContinuationIndentWidth:                   8
 IndentCaseLabels:                          false
 IndentWidth:                               8
+PenaltyReturnTypeOnItsOwnLine:             1000
 SortIncludes:                              false
 UseTab:                                    Always