bug#74647: 31.0.50; Build failure on master w/ librsvg-2.58.5

[Eli Zaretskii <eliz@gnu.org>]

> Cc: Manuel Giraud <manuel@ledu-giraud.fr>
> From: Sam James <sam@gentoo.org>
> Date: Mon, 02 Dec 2024 11:45:41 +0000
> 
> I see the following build failure (with a clean bootstrap) with librsvg-2.58.5 on master:
> """
> image.c: In function ‘svg_load_image’:
> image.c:12358:12: error: implicit declaration of function ‘rsvg_handle_get_pixbuf_and_error’; did you mean ‘rsvg_handle_get_pixbuf_sub’? [-Wimplicit-function-declaration]
> 12358 |   pixbuf = rsvg_handle_get_pixbuf_and_error (rsvg_handle, &err);
>       |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>       |            rsvg_handle_get_pixbuf_sub
> image.c:12358:12: warning: nested extern declaration of ‘rsvg_handle_get_pixbuf_and_error’ [-Wnested-externs]
> image.c:12358:10: error: assignment to ‘GdkPixbuf *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
> 12358 |   pixbuf = rsvg_handle_get_pixbuf_and_error (rsvg_handle, &err);
>       |          ^
> make[2]: *** [Makefile:457: image.o] Error 1
> make[2]: *** Waiting for unfinished jobs....
> """
> 
> I've attached the full build.log. Let me know if you need more information.

Manuel, I guess the version guard needs some adjustment?  Which
version of librsvg introduced rsvg_handle_get_pixbuf_and_error?