i2c: Improve size determinations

[ Upstream commit 06e98957 ]

Replace the specification of a data structure by a pointer dereference
as the parameter for the operator "sizeof" to make the corresponding
size determination a bit safer according to the Linux coding style
convention.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Stable-dep-of: 05f933d5 ("i2c: nomadik: Remove a useless call in the remove function")
Signed-off-by: Sasha Levin <sashal@kernel.org>