net: dsa: mv88e6xxx: fix up kerneldoc some more

Commit 0b529448

 ("net: dsa: mv88e6xxx: scratch: Fixup kerneldoc")
has addressed some but not all kerneldoc warnings for the Global 2
Scratch register accessors. Namely, we have some mismatches between
the function names in the kerneldoc and the ones in the actual code.
Let's adjust the comments so that they match the functions they're
sitting next to.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>