mfd: max8998: Make it explicitly non-modular

mfd: max8998: Make it explicitly non-modular

The Kconfig currently controlling compilation of this code is:

mfd/Kconfig:config MFD_MAX8998
mfd/Kconfig:    bool "Maxim Semiconductor MAX8998/National LP3974 PMIC Support"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

We explicitly disallow a driver unbind, since that doesn't have a
sensible use case anyway, and it allows us to drop the ".remove"
code for non-modular drivers.

Since module_init was not in use by this code, the init ordering
remains unchanged with this commit.

We delete the include of module.h as well as an unused include of
moduleparam.h too.

Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.

We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>