clk: msm: remove unused clock drivers

Krait CPU support is not present is no longer present in the
kernel. Delete the clock drivers associated with these CPUs.

Similarly, 8994 support is also no longer present, remove
its clock drivers also.

Change-Id: If80992ea1ac3351cc71af3f3f214f616dff00629
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>