net: marvell: prestera: Correct typo

The function was incorrectly named with a trailing 'r' at the end of
prestera.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20210109050622.8081-1-f.fainelli@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>