cpufreq: dt-platdev: add missing MODULE_DESCRIPTION() macro

[ Upstream commit 64e018d7 ]

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cpufreq/cpufreq-dt-platdev.o

Add the missing invocation of the MODULE_DESCRIPTION() macro.

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Stable-dep-of: f1f010c9 ("cpufreq: fix using cpufreq-dt as module")
Signed-off-by: Sasha Levin <sashal@kernel.org>