drm/msm: Remove non-DT code in msm_drv

Support for non-DT kernels was mainly to use v3.4 downstream kernels.
This is no longer a priority now as we have reasonable support upstream.

Remove CONFIG_OF from the top level msm_drv.c file. While we're at it,
clean up the data matching process using of_device_get_match_data.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>