media: i2c: imx274: fix trivial typo expsoure/exposure

Fix typo expsoure/exposure

Fixes: 0985dd30 ("media: imx274: V4l2 driver for Sony imx274 CMOS sensor")
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>