UBUNTU: SAUCE: (no-up) Allow filtering of cpufreq drivers

Harmless patch that allows k8 powernow machines to boot. Carry until
conflict.

BugLink: http://bugs.launchpad.net/bugs/984288

Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Herton Krzesinski <herton.krzesinski@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
[ arighi: context adjustment (cpu0_hotplug has been removed) ]
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>

Documentation/admin-guide/kernel-parameters.txt

@@ -848,6 +848,10 @@
 			Format:
 			<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
 
+	cpufreq_driver= [X86] Allow only the named cpu frequency scaling driver
+			to register. Example: cpufreq_driver=powernow-k8
+			Format: { none | STRING }
+
 	cpuidle.off=1	[CPU_IDLE]
 			disable the cpuidle sub-system