drm/amd/display: remove useless FPU protection wrapper from dcn31_resource file

Many lines of code in dcn31_resource_construct are wrapped by DC_FP
macro to protect FPU operations; however, there is no FPU in this
region. Therefore, just remove the wrapper for clarity.

Signed-off-by: Melissa Wen <mwen@igalia.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>