net: ieee802154: ca8210: Fix lifs/sifs periods

These periods are expressed in time units (microseconds) while 40 and 12
are the number of symbol durations these periods will last. We need to
multiply them both with the symbol_duration in order to get these
values in microseconds.

Fixes: ded845a7

 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220201180629.93410-2-miquel.raynal@bootlin.com


Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>