docs: Add missing state parameter to machine.enable_irq docs.

docs/machine.rst

@@ -64,7 +64,7 @@ Functions
     original state, before :func:`machine.disable_irq()` was called.
 
 
-.. method:: machine.enable_irq()
+.. method:: machine.enable_irq(state)
 
     Re-enable interrupt requests. The *state* parameter should be the value 
     that was returned from the most recent call to the
@@ -96,4 +96,4 @@ The ``machine`` module allows you to read from the device's memory, getting 1
 byte (8 bits; ``mem8``), 2 byte (16 bits; ``mem16``), or 4 byte (32 bits; 
 ``mem32``) words from physical addresses. For example: ``mem8[0x00]`` reads 1 
 byte on physical address ``0x00``. This has a number of uses, for example if 
-you'd like to read data from the nRF51 registers.
+you'd like to read data from the nRF51 registers.