intellidemand: tweak optimal for krait 600 series

Signed-off-by: Paul Reioux <reioux@gmail.com>
Signed-off-by: aatjitra <aatjitra@gmail.com>
intellidemand: set default sampling rate to 50k

Signed-off-by: Paul Reioux <reioux@gmail.com>
Signed-off-by: aatjitra <aatjitra@gmail.com>

Conflicts:
	drivers/cpufreq/cpufreq_intellidemand.c