docs/psoc6/quickref: Documented gpio deinit function.

Signed-off-by: NikhitaR-IFX <nikhita.rajasekhar@infineon.com>

Author: NikhitaR-IFX

docs/psoc6/quickref.rst

@@ -155,6 +155,12 @@ Trigger can be ``Pin.IRQ_FALLING`` or ``Pin.IRQ_RISING`` or ``PIN.IRQ_FALLING |
 
 Set pin value to its complement.
 
+.. method:: Pin.deinit()
+
+Deinitializes the pin object. This will release any resources associated with it. The pin object created from MicroPython side would still be available, but it will not be functional anymore. 
+The pin can be re-initialised by calling the :meth:`Pin.init` function.
+
+
 Signal 
 ^^^^^^