core: remove leftovers of the removed options

a follow-up for fb312bd

src/config.h

@@ -249,8 +249,6 @@ typedef struct options {
 	bool glx_no_stencil;
 	/// Whether to avoid rebinding pixmap on window damage.
 	bool glx_no_rebind_pixmap;
-	/// Custom fragment shader for painting windows, as a string.
-	char *glx_fshader_win_str;
 	/// Whether to detect rounded corners.
 	bool detect_rounded_corners;
 	/// Force painting of window content with blending.

src/config_libconfig.c

@@ -830,16 +830,6 @@ bool parse_config_libconfig(options_t *opt, const char *config_file) { /*NOLINT(
 	config_lookup_float(&cfg, "frame-opacity", &opt->frame_opacity);
 	// -c (shadow_enable)
 	lcfg_lookup_bool(&cfg, "shadow", &opt->shadow_enable);
-	// -m (menu_opacity)
-	if (config_lookup_float(&cfg, "menu-opacity", &dval)) {
-		log_warn("Option `menu-opacity` is deprecated, and will be removed."
-		         "Please use the wintype option `opacity` of `popup_menu`"
-		         "and `dropdown_menu` instead.");
-		opt->wintype_option[WINTYPE_DROPDOWN_MENU].opacity = dval;
-		opt->wintype_option[WINTYPE_POPUP_MENU].opacity = dval;
-		opt->wintype_option_mask[WINTYPE_DROPDOWN_MENU].opacity = true;
-		opt->wintype_option_mask[WINTYPE_POPUP_MENU].opacity = true;
-	}
 	// -f (fading_enable)
 	if (config_lookup_bool(&cfg, "fading", &ival)) {
 		opt->fading_enable = ival;

src/options.c

@@ -794,11 +794,6 @@ static bool sanitize_options(struct options *opt) {
 		return false;
 	}
 
-	if (opt->glx_fshader_win_str) {
-		log_warn("--glx-fshader-win has been replaced by "
-		         "\"--window-shader-fg\" for the new backends.");
-	}
-
 	if (opt->max_brightness < 1.0 && opt->use_damage) {
 		log_warn("--max-brightness requires --no-use-damage. "
 		         "Falling back to 1.0.");
@@ -975,7 +970,6 @@ void options_destroy(struct options *options) {
 		free(options->blur_kerns[i]);
 	}
 	free(options->blur_kerns);
-	free(options->glx_fshader_win_str);
 
 	dynarr_free(options->all_scripts, script_ptr_deinit);
 	memset(options->animations, 0, sizeof(options->animations));