Floating point twiddle factors

Use floating point twiddle for first 8 butterflies in 16 point DFT.
Later stages like 256 point DFT use floating point twiddle only in first
4 butterflies. Doing so reduces EVM in first 4 frequency bins by 6 times
for 1024 DFT.

openair1/PHY/TOOLS/dfts_load.c

@@ -100,8 +100,7 @@ uint32_t IDFT_SCALING_3072[2][4] = {{1, 1, 1, 3}, {1, 1, 1, 3}};
 #endif
 
 uint32_t DFT_SCALING_16[][1] = {{2}};
-uint32_t DFT_SCALING_64[5][2]   = {{3,0},{2,1},{1,2},{1,2},{1,2}};
-uint32_t DFT_SCALING_128[5][3]  = {{4,0,0},{3,1,0},{2,2,0},{1,3,0},{0,4,0}};
+uint32_t DFT_SCALING_64[5][2] = {{3, 0}, {2, 1}, {1, 2}, {1, 2}, {1, 2}};
 uint32_t DFT_SCALING_256[5][3]  = {{4,0,0},{3,1,0},{2,2,0},{1,3,0},{0,4,0}};
 int32_t DFT_SCALING_512_THRES[7] = {53, 57, 59, 63, 65, 69, 100};
 int32_t DFT_SCALING_1024_THRES[5] = {49,55,63,69,100};