fix: Show underlying unavailable entity colors (#1923)

- Closes #1906

src/scss/icon.scss

@@ -22,5 +22,4 @@ svg path {
 
 :host([allow-override-non-active-styles]) state-badge {
   --state-inactive-color: inherit;
-  --state-unavailable-color: inherit;
 }

src/scss/menu-button.scss

@@ -4,7 +4,6 @@ ha-icon-button {
   // Icons in the menu are expected to follow Advanced Camera Card theming
   // unless they are active (in which case we want to take advantage of the
   // whatever styling is appropriate, e.g. light icon partially lit).
-  --state-unavailable-color: var(--advanced-camera-card-button-color);
   --state-inactive-color: var(--advanced-camera-card-button-color);
 
   color: var(--advanced-camera-card-menu-button-inactive-color);

src/scss/submenu.scss

@@ -1,4 +1,4 @@
-@use './button.scss';
+@use './menu-button.scss';
 @import './z-index.scss';
 
 :host {
@@ -6,14 +6,3 @@
 
   --mdc-menu-z-index: #{$z-index-submenu};
 }
-
-ha-icon-button {
-  // The main submenu icon is expected to follow Advanced Camera Card theming unless it
-  // is are active (in which case we want to take advantage of the whatever
-  // styling is appropriate, e.g. light icon partially lit).
-  --state-unavailable-color: var(--advanced-camera-card-button-color);
-  --state-inactive-color: var(--advanced-camera-card-button-color);
-
-  color: var(--advanced-camera-card-menu-button-inactive-color);
-  background-color: var(--advanced-camera-card-menu-button-background);
-}