ethernet: ti: cpts: Use devm_kcalloc() instead of devm_kzalloc()

Use 2-factor multiplication argument form devm_kcalloc() instead
of devm_kzalloc().

Link: https://github.com/KSPP/linux/issues/162


Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20211006181115.GA913499@embeddedor


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