staging: octeon: cleanup unnecessary parentheses in ethernet-spmi.c

checkpatch.pl reported issue of unnecessary parentheses for the
expression. It has been removed to fix the report.

Signed-off-by: Shreesh Adiga <16567adigashreesh@gmail.com>
Link: https://lore.kernel.org/r/20210219170737.1138083-1-16567adigashreesh@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>