bug#51296: [PATCH] Add WebP format support

[Eli Zaretskii <eliz@gnu.org>]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Thu, 21 Oct 2021 11:36:45 -0700
> Cc: 51296@debbugs.gnu.org
> 
> >> +      contents = (uint8_t*) SSDATA (specified_data);
> >
> > Space before '*' again.  Also, is the type cast really needed?  If
> > not, it is better to drop it.
> 
> Fixed the style issue.
> 
> The cast fixes this warning, so I kept it and added a comment saying
> "Casting avoids a GCC warning":
> 
> image.c: In function ‘webp_load’:
> image.c:8878:16: warning: pointer targets in assignment from ‘char *’
> to ‘uint8_t *’ {aka ‘unsigned char *’} differ in signedness
> [-Wpointer-sign]
>  8878 |       contents = SSDATA (specified_data);
>       |                ^

And if you use SDATA instead of SSDATA?

Otherwise, I think this is good to go, thanks.