From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Date: Thu, 9 Aug 2018 10:47:20 -0500

> In preparation to enabling -Wimplicit-fallthrough, mark switch cases
> where we are expecting to fall through.
> 
> Notice that in this particular case, I placed the "fall through"
> annotation at the bottom of the case, which is what GCC is expecting
> to find.
> 
> Addresses-Coverity-ID: 115075 ("Missing break in switch")
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Applied.