Revert "Fix selection of fonts that don't have regular weight"

This reverts commit 1b2511fa2a.
That commit caused unintended regressions which are worse
than the problem it attempted to fix.  See the discussion at

  https://lists.gnu.org/archive/html/emacs-devel/2021-12/msg01643.html

for the details.

src/font.c

@@ -2768,6 +2768,7 @@ font_delete_unmatched (Lisp_Object vec, Lisp_Object spec, int size)
 	      int candidate = XFIXNUM (AREF (entity, prop)) >> 8;
 
 	      if (candidate != required
+#ifdef HAVE_NTGUI
 		  /* A kludge for w32 font search, where listing a
 		     family returns only 4 standard weights: regular,
 		     italic, bold, bold-italic.  For other values one
@@ -2777,14 +2778,10 @@ font_delete_unmatched (Lisp_Object vec, Lisp_Object spec, int size)
 		     weight, so if we require exact match, the
 		     non-regular font will be rejected.  So we relax
 		     the accuracy of the match here, and let
-		     font_sort_entities find the best match.
-
-		     Similar things happen on Posix platforms, when
-		     people use font families that don't have the
-		     regular weight, only the medium weight: these
-		     families get rejected if we require an exact match.  */
+		     font_sort_entities find the best match.  */
 		  && (prop != FONT_WEIGHT_INDEX
 		      || eabs (candidate - required) > 100)
+#endif
 		  )
 		prop = FONT_SPEC_MAX;
 	    }