Fix PWM slice calculation for RP2350 in RP.PWM.To_PWM#76
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The function performed Shift_Right (Pin, 1) but then ignored the shifted value and overwrote Slice with "Pin and 2#111#". The fix now correctly uses the already shifted value for the mask operation (Slice and 2#111#). This matches the RP2350 datasheet and resolves incorrect slice assignments (e.g. GPIO14 was mapped to slice 6 instead of 7), which caused missing or flickering PWM outputs when pins shared a slice on the Pico 2.
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The function performed a Shift_Right (Pin, 1) but then ignored the result and overwrote Slice with:
for all pins below 32. The fix uses the already shifted value for the mask operation:
This brings the calculation in line with the RP2350 PWM GPIO mapping table in the datasheet.
Tested on Raspberry Pi Pico 2 (RP2350):
The change eliminates slice misconfiguration when multiple GPIOs share
the same PWM slice, which previously caused missing or flickering PWM
outputs on the Pico 2.