coding-style.rst: Avoid comma statements

Commas are not how statements are terminated.
Always use semicolons and braces if necessary.

Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/2a97b738bba335434461a5a918053a49c1fb6af4.1598331148.git.joe@perches.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/process/coding-style.rst

@@ -69,9 +69,26 @@ something to hide:
 	if (condition) do_this;
 	  do_something_everytime;
 
+Don't use commas to avoid using braces:
+
+.. code-block:: c
+
+	if (condition)
+		do_this(), do_that();
+
+Always uses braces for multiple statements:
+
+.. code-block:: c
+
+	if (condition) {
+		do_this();
+		do_that();
+	}
+
 Don't put multiple assignments on a single line either.  Kernel coding style
 is super simple.  Avoid tricky expressions.
 
+
 Outside of comments, documentation and except in Kconfig, spaces are never
 used for indentation, and the above example is deliberately broken.