ARM: configs: tizen_bcm2711_defconfig: Enable CONFIG_CPUFREQ_DT config

ARM: configs: tizen_bcm2711_defconfig: Enable CONFIG_CPUFREQ_DT config

The cpufreq subsystem provides the generic cpufreq driver
based on device-tree, CONFIG_CPUFREQ_DT config. Enable CONFIG_CPUFREQ_DT
to support cpufreq driver instead of BCM legacy driver. By using
CONFIG_CPUFREQ_DT, be able to use the features provided by other linux kernel
framework like thermal. And control the fine-grained CPU frequency with 4 step
as following:

[Before available CPU frequencies]
600000
1500000

[After available CPU frequencies]
600000
700000
1000000
1500000

Change-Id: I3119b54d82822da9bbf0c2ddd6b2fbb17389b7cf
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>