libmvec: further unifdef'ing (LIBMVEC_SO_BUILD)

*** 27,41 ****
   */
  
          .file   "__vlog_ultra3.S"
  
  #include "libm.h"
- #if defined(LIBMVEC_SO_BUILD)
          .weak   __vlog
          .type   __vlog,#function
          __vlog = __vlog_ultra3
- #endif
  
  /*
   * ELEVENBIT table and order 5 POLYNOMIAL no explicit correction t
   */
  
--- 27,39 ----