drivers/cpuidle: make cpuidle-clps711x.c explicitly non-modular

The Kconfig currently controlling compilation of this code is:

drivers/cpuidle/Kconfig.arm:config ARM_CLPS711X_CPUIDLE
drivers/cpuidle/Kconfig.arm:    bool "CPU Idle Driver for CLPS711X processors"

...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_platform_driver() uses the same init level priority as
builtin_platform_driver() the init ordering remains unchanged with
this commit.

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.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>