[PATCH] cifs: Convert to use the fallthrough macro

[Joe Perches]

On Sun, 2020-08-09 at 11:46 -0500, Steve French wrote:
> Is this conversion from "/* Fallthrough */"   to the preferred (?)
> "fallthrough;" documented anywhere?

Documentation/process/deprecated.rst

As there have been a long list of flaws `due to missing "break" statements
<https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow
implicit fall-through. In order to identify intentional fall-through
cases, we have adopted a pseudo-keyword macro "fallthrough" which
expands to gcc's extension `__attribute__((__fallthrough__))
<https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_.