drivers/staging: make android lowmemorykiller.c explicitly non-modular

The Kconfig currently controlling compilation of this code is:

drivers/staging/android/Kconfig:config ANDROID_LOW_MEMORY_KILLER
drivers/staging/android/Kconfig:        bool "Android Low Memory Killer"

...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.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We replace module.h with init.h and moduleparam.h ; the latter since
this file was previously implicitly relying on getting that header.

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

Cc: "Arve Hjønnevåg" <arve@android.com>
Cc: Riley Andrews <riandrews@android.com>
Cc: devel@driverdev.osuosl.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>