Clang-Tidy warning fixes.

* src/base/ftobjs.c (FT_Get_Paint): Operator has equivalent nested operands.
* src/bdf/bdflib.c (_bdf_add_property): Value stored to `fp` is never read.
* src/sdf/ftbsdf.c (bsdf_init_distance_map): Value stored to `pixel` is
never read.
* src/sdf/ftsdf.c (split_sdf_shape): Value stored to `error` is never read.

src/base/ftobjs.c

@@ -5729,7 +5729,7 @@
     SFNT_Service  sfnt;
 
 
-    if ( !face || !paint || !paint )
+    if ( !face || !paint )
       return 0;
 
     if ( !FT_IS_SFNT( face ) )

src/bdf/bdflib.c

@@ -1174,7 +1174,6 @@
                             font->props_size + 1 ) )
         goto Exit;
 
-      fp = font->props + font->props_size;
       font->props_size++;
     }
 

src/sdf/ftbsdf.c

@@ -756,8 +756,6 @@
             byte  = (FT_Byte)( 1 << mod );
 
             t[t_index].alpha = pixel & byte ? 255 : 0;
-
-            pixel = 0;
           }
         }
       }

src/sdf/ftsdf.c

@@ -1277,9 +1277,11 @@
 
         default:
           error = FT_THROW( Invalid_Argument );
-          goto Exit;
         }
 
+        if ( error != FT_Err_Ok )
+          goto Exit;
+
         edges = edges->next;
       }