SW-382: Replace Python2 integer division (/) with Python3 one (//)

LCU/checkhardware/checkhardware_lib/spectrum_checks/tools.py

@@ -16,4 +16,4 @@ def psd(data, sampletime):
     n = fft_data.size
     psd_freq = fft.fftfreq(n, sampletime)
     _psd = power(abs(fft_data), 2) / n
-    return _psd[:n / 2], psd_freq[:n / 2]
+    return _psd[:n // 2], psd_freq[:n // 2]