Remove two duplicated named asm constraints.

This fixes compilation of libmpcodecs/vf_fspp.c with gcc and
INLINE_ASM_DIRECT_SYMBOL_REFS disabled.

libavfilter/libmpcodecs/vf_fspp.c

@@ -1601,7 +1601,7 @@ static void column_fidct_mmx(int16_t* thr_adr,  int16_t *data,  int16_t *output,
           NAMED_CONSTRAINTS_ADD(ff_MM_FIX_0_707106781,MM_2,MM_FIX_1_414213562_A,MM_FIX_1_414213562,MM_FIX_0_382683433,
           ff_MM_FIX_0_541196100,MM_FIX_1_306562965,MM_FIX_0_847759065)
           NAMED_CONSTRAINTS_ADD(MM_FIX_0_566454497,MM_FIX_0_198912367,MM_FIX_2_613125930,MM_FIX_1_847759065,
-          MM_FIX_1_082392200,ff_MM_FIX_0_541196100,MM_FIX_1_306562965)
+          MM_FIX_1_082392200)
         : "%"REG_a
         );
 }