media: atomisp: mt9m114: replace fixed function names

There are a couple of debug messages using hardcoded function names
instead of the preferred __func__ magic constant.

Replace them:

WARNING: Prefer using '"%s...", __func__' to using 'misensor_rmw_reg', this function's name, in a string
215: FILE: ./media/atomisp/i2c/atomisp-mt9m114.c:215:
+       v4l2_err(client, "misensor_rmw_reg error exit, read failed\n");

WARNING: Prefer using '"%s...", __func__' to using 'misensor_rmw_reg', this function's name, in a string
236: FILE: ./media/atomisp/i2c/atomisp-mt9m114.c:236:
+       v4l2_err(client, "misensor_rmw_reg error exit, write failed\n");

Signed-off-by: Juan Antonio Aldea-Armenteros <juant.aldea@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>