qcom-cpufreq: skip frequencies that round to same rate

Since not all frequencies line up between speed bins,
the common cpufreq table sometimes has frequencies
that round up the same actual frequency.

Fix this by skipping those frequencies.

Change-Id: I0516cc67a1343150f3d1f838b9d9b329e8e1e498
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
Signed-off-by: David Keitel <dkeitel@codeaurora.org>