Add updated intel_idle driver

[Leann Ogasawara]

SRU Justification:

As part of the linux-backports-modules package, we periodically provide updated drivers to provide additional support for hardware and provide bug fixes. The intel_idle is a cpuidle driver that loads on specific Intel processors in lieu of the legacy ACPI processor_idle driver. The intent is to make Linux more efficient on these processors, as intel_idle knows more than ACPI, as well as make Linux more immune to ACPI BIOS bugs. As we now support HW that can leverage the intel_idle driver, it's advantageous to provide an updated version of the driver for those interested in it's use. All of the patches are already upstream as well (see details below).

Impact:
linux-backports-modules is an elective install so the risk of regression should be small. Additionally, and these patches only touches a specific driver. This driver can also be disabled by booting with "intel_idle.max_cstate=0" which disables intel_idle and the system will fall back on ACPI's "acpi_idle".

Test Case: Install the linux-backports-modules-idle package.

A summary of the usptream patches is as follows:

 * intel_idle: do not use the LAPIC timer for ATOM C2
 * intel_idle: add initial Sandy Bridge support
 * intel_idle: delete bogus data from cpuidle_state.power_usage
 * intel_idle: simplify test for leave_mm()
 * intel_idle: enable Atom C6
 * intel_idle: Voluntary leave_mm before entering deeper
 * intel_idle: add missing __percpu markup
 * intel_idle: Change mode 755 => 644
 * intel_idle: recognize Lincroft Atom Processor
 * intel_idle: add support for Westmere-EX
 * intel_idle: delete power_policy modparam, and choose substate functions
 * intel_idle: delete substates DEBUG modparam

[Leann Ogasawara (leannogasawara)]

Backporting intel_idle for LBM won't work at the moment. Testing has proven that because the acpi_idle driver is built into the kernel, it prevents the intel_idle driver from loading later on via LBM. This is because the core cpuidle driver is not capable of handling run-time changing of idle drivers. As a result, I will pursue getting these patches applied as a regular SRU to the Maverick kernel.