Update adafruit_as7341.py

The "F8R" needs to be connected to ADC3 not ADC2. Fixing this solves the issue of F8 channel reading being wrong. I have double checked this with the c++ code and with an actual spectrometer.

Author: afaghm

adafruit_as7341.py

@@ -462,7 +462,7 @@ def _f5f8_clear_nir(self):
         self._set_smux(SMUX_IN.NC_NC1, SMUX_OUT.DISABLED, SMUX_OUT.DISABLED)
         self._set_smux(SMUX_IN.NC_F2R, SMUX_OUT.DISABLED, SMUX_OUT.DISABLED)
         self._set_smux(SMUX_IN.F4R_NC, SMUX_OUT.DISABLED, SMUX_OUT.DISABLED)
-        self._set_smux(SMUX_IN.F8R_F6R, SMUX_OUT.ADC2, SMUX_OUT.ADC1)
+        self._set_smux(SMUX_IN.F8R_F6R, SMUX_OUT.ADC3, SMUX_OUT.ADC1)
         self._set_smux(SMUX_IN.NC_F3R, SMUX_OUT.DISABLED, SMUX_OUT.DISABLED)
         self._set_smux(SMUX_IN.F1R_EXT_GPIO, SMUX_OUT.DISABLED, SMUX_OUT.DISABLED)
         self._set_smux(SMUX_IN.EXT_INT_CR, SMUX_OUT.DISABLED, SMUX_OUT.ADC4)