bug#62518: 30.0.50; Misc Build Warnings

[Eli Zaretskii <eliz@gnu.org>]

> From: Jacob Faibussowitsch <jacob.fai@gmail.com>
> Date: Wed, 29 Mar 2023 08:38:59 -0400
> 
> Building C src
> --------------
> 
> dispnew.c:3650:12: warning: variable 'changed_p' set but not used [-Wunused-but-set-variable]
>       bool changed_p = 0, mouse_face_overwritten_p = 0;
>            ^
> 
> Building Lisp src
> -----------------
> 
> dynamic-setting.el:58:12: Warning: the function ‘reconsider-frame-fonts’ is not known to be defined.
> 
> image/wallpaper.el:455:35: Warning: the function ‘x-open-connection’ is not known to be defined.
> 
> net/eww.el:1205:59: Warning: the function ‘imagep’ is not known to be defined.
> 

These are because you build --without-x.  They are harmless.

> In org-table-make-reference:
> org/org-table.el:2864:23: Warning: ‘eq’ called with literal string that may never match (arg 2)
> 
> In org-remove-timestamp-with-keyword:
> org/org.el:10218:14: Warning: ‘backward-delete-char’ is for interactive use only; use ‘delete-char’ instead.
> 
> In org-fast-tag-selection:
> org/org.el:12009:22: Warning: ‘condition-case’ without handlers
> 
> In org-delete-backward-char:
> org/org.el:16535:8: Warning: ‘backward-delete-char’ is for interactive use only; use ‘delete-char’ instead.

These are real (though minor) problems, but Org is developed
elsewhere, and has requirements to support older Emacs versions, so
I'll defer to the Org developers (CC'ed) to do TRT about these.

Thanks.