PM: EM: update Kconfig description and drop "default n" option

Energy Model supports now other devices like GPUs, DSPs, not only CPUs.
Thus, update the description in the config option. Remove also unneeded
"default n". If the "default" line is removed, it defaults to 'n'.
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

kernel/power/Kconfig

@@ -322,15 +322,14 @@ config CPU_PM
 	bool
 
 config ENERGY_MODEL
-	bool "Energy Model for CPUs"
+	bool "Energy Model for devices with DVFS (CPUs, GPUs, etc)"
 	depends on SMP
 	depends on CPU_FREQ
-	default n
 	help
 	  Several subsystems (thermal and/or the task scheduler for example)
-	  can leverage information about the energy consumed by CPUs to make
-	  smarter decisions. This config option enables the framework from
-	  which subsystems can access the energy models.
+	  can leverage information about the energy consumed by devices to
+	  make smarter decisions. This config option enables the framework
+	  from which subsystems can access the energy models.
 
 	  The exact usage of the energy model is subsystem-dependent.