drm/amd/display: make dscl32_calc_lb_num_partitions static

This symbol is not used outside of dcn32_dpp.c, so marks it static.

drivers/gpu/drm/amd/amdgpu/../display/dc/dcn32/dcn32_dpp.c:34:6: warning: no previous prototype for ‘dscl32_calc_lb_num_partitions’.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2118


Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>