drm/msm: add a kernel param to select between MDP5 and DPU drivers

For some of the platforms (e.g. SDM660, SDM630, MSM8996, etc.) it is
possible to support this platform via the DPU driver (e.g. to provide
support for DP, multirect, etc). Add a modparam to be able to switch
between these two drivers.

All platforms supported by both drivers are by default handled by the
MDP5 driver. To let them be handled by the DPU driver pass the
`msm.prefer_mdp5=false` kernel param.

Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Carl Vanderlip <quic_carlv@quicinc.com>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/577504/
Link: https://lore.kernel.org/r/20240208-fd-migrate-mdp5-v4-3-945d08ef3fa8@linaro.org