[css-color-5] Serialize color-mix in hsl and hwb to maximise precision, fix w3c#6860

Author: svgeesus

css-color-5/Overview.bs

@@ -2465,11 +2465,11 @@ is the same as that specified in
 	</tr>
 	<tr>
 		<td>hsl</td>
-		<td>hsl(h s l) <a href="#fn1">¹</a></td>
+		<td>color(srgb r g b) </td>
 	</tr>
 	<tr>
 		<td>hwb</td>
-		<td>hwb(h w b) <a href="#fn2">²</a></td>
+		<td>color(srgb r g b)</td>
 	</tr>
 	<tr>
 		<td>xyz-d65</td>
@@ -2481,7 +2481,7 @@ is the same as that specified in
 	</tr>
 	<tr>
 		<td>xyz</td>
-		<td>color(xyz-d65 x y z) <a href="#fn3">³</a></td>
+		<td>color(xyz-d65 x y z) <a href="#fn1">¹</a></td>
 	</tr>
 	<tr>
 		<td>lab</td>
@@ -2503,10 +2503,6 @@ is the same as that specified in
 
 <dl>
 	<dt id="fn1">¹</dt>
-	<dd>''hsl()'' will then serialize as ''rgb()'' or ''rgba()''</dd>
-	<dt id="fn2">²</dt>
-	<dd>''hwb()'' will then serialize as ''rgb()'' or ''rgba()''</dd>
-	<dt id="fn3">³</dt>
 	<dd>Because ''xyz'' is just an alias for ''xyz-d65''</dd>
 
 </dl>