drm/msm/mdp5: Remove MSM8974v1

drm/msm/mdp5: Remove MSM8974v1

To the best of my knowledge, the v1 version of this SoC had been
superseded before any device was released on the market. Everywhere
else in the kernel, there are assumptions about the SoC being revision
2 or the later MSM8974PRO.

Remove the config for that flavor of MDP. To bring the naming in line
with the rest of the kernel, remove the v2 suffix from the remaining
config.

Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/708112/
Link: https://lore.kernel.org/r/20260302-topic-goodnight_8974v1-v1-1-e0006f7a0526@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>