drm/msm/mdp5: make config variables static

drm/msm/mdp5: make config variables static

A number of the config structs are not exported so make
them static to avoid the following sparse warnings:

drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c:17:26: warning: symbol 'msm8x74v1_config' was not declared. Should it be static?
drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c:101:26: warning: symbol 'msm8x74v2_config' was not declared. Should it be static?
drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c:183:26: warning: symbol 'apq8084_config' was not declared. Should it be static?
drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c:278:26: warning: symbol 'msm8x16_config' was not declared. Should it be static?
drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c:345:26: warning: symbol 'msm8x94_config' was not declared. Should it be static?
drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c:440:26: warning: symbol 'msm8x96_config' was not declared. Should it be static?
drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c:548:26: warning: symbol 'msm8917_config' was not declared. Should it be static?
drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c:633:26: warning: symbol 'msm8998_config' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191009120522.17019-1-ben.dooks@codethink.co.uk
Link: https://patchwork.freedesktop.org/patch/msgid/20190918195722.2149227-1-arnd@arndb.de