xfce4-cpu-freq currently only has KEYWORDS="~amd64 ~hppa ~ppc ~x86". xfce-base/xfce4-extras depends on this with USE="cpufreq". So please, either keyword on your arch, or use.mask cpufreq.
cpufreq was already masked on Feb 2 for sparc...
USE="cpufreq" and dep was temporarily removed from xfce4-extras ebuild so that 4.4.0 could be unmasked. It will be readded once this bug is fixed.
added ~ppc64
Asked GMsoft to remove ~hppa, and he did. I'm closing this as I really doubt arch teams left here do CPU Frequency Scaling and if they do they can keyword as-needed basis.
proper resolution.
*** This bug has been marked as a duplicate of bug 175749 ***