staging: greybus: Replace gcam macros with direct dev log calls

Reported by checkpatch:

CHECK: Macro argument 'gcam' may be better as '(gcam)' to avoid
precedence issues

Inline standard calls to 'dev_*' kernel logging functions, in favor
of 'gcam_*' macros, to clear up gcam-related logging.

Signed-off-by: Jackson Chui <jacksonchui.qwerty@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/ZhRzWNiak1qOdJLL@jc-ubuntu-dev-korn-1


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>