ossl_seed: remove leftover RAND_screen check

Before commit 2dded8fedb (dec 2010) there was logic that used
RAND_screen() at times and now I remove the leftover #ifdef check for
it.

The seeding code that uses Curl_FormBoundary() in ossl_seed() is dubious
to keep since it hardly increases randomness but I fear I'll break
something if I remove it now...

lib/ssluse.c

@@ -237,11 +237,6 @@ static int ossl_seed(struct SessionHandle *data)
 
   /* If we get here, it means we need to seed the PRNG using a "silly"
      approach! */
-#ifdef HAVE_RAND_SCREEN
-  /* if RAND_screen() is present, this is windows and thus we assume that the
-     randomness is already taken care of */
-  nread = 100; /* just a value */
-#else
   {
     int len;
     char *area;
@@ -263,7 +258,6 @@ static int ossl_seed(struct SessionHandle *data)
       free(area); /* now remove the random junk */
     } while(!RAND_status());
   }
-#endif
 
   /* generates a default path for the random seed file */
   buf[0]=0; /* blank it first */