Simplified some inner loop calcs
Simplified some inner loop calcs


'make test' output:
### testing SNR for  1024 point FFTs
#### DOUBLE
snr_t2f = 295.34
snr_f2t = 308.77
#### FLOAT
snr_t2f = 146.93
snr_f2t = 143.56
#### SHORT
snr_t2f = 54.799
snr_f2t = 24.562

#### timing 10000 x 1024 point FFTs
#### DOUBLE
Elapsed:0:10.69 user:8.71 sys:0.20
#### FLOAT
Elapsed:0:04.40 user:3.42 sys:0.11
#### SHORT
Elapsed:0:05.62 user:4.77 sys:0.04

pemryan/kissFFT,sf-is-evil/kissfft,pemryan/kissFFT,sf-is-evil/kissfft,sf-is-evil/kissfft,sf-is-evil/kissfft,pemryan/kissFFT,pemryan/kissFFT