msm: mdss: remove deprecated compression ratio support

Starting with the change: "msm: mdss: use compression
ratio factors passed by user space"; compression ratio
factors are now assigned and passed by user space, so
kernel side does not need to assign the compression ratio
factors anymore. This change removes the deprecated
kernel code that was assigning the compression ratio.

Change-Id: I93e7afefa99198d947746df4a6962d0bb3508375
Signed-off-by: Ingrid Gallardo <ingridg@codeaurora.org>