drm/amdgpu/display: use GFP_ATOMIC in dcn21_validate_bandwidth_fp()

After fixing nested FPU contexts caused by 41401ac67791 we're still seeing
complaints about spurious kernel_fpu_end(). As it turns out this was
already fixed for dcn20 in commit f41ed88cbd ("drm/amdgpu/display:
use GFP_ATOMIC in dcn20_validate_bandwidth_internal") but never moved
forward to dcn21.

Signed-off-by: Holger Hoffstätte <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c

···
 	int vlevel = 0;
 	int pipe_split_from[MAX_PIPES];
 	int pipe_cnt = 0;
-	display_e2e_pipe_params_st *pipes = kzalloc(dc->res_pool->pipe_count * sizeof(display_e2e_pipe_params_st), GFP_KERNEL);
+	display_e2e_pipe_params_st *pipes = kzalloc(dc->res_pool->pipe_count * sizeof(display_e2e_pipe_params_st), GFP_ATOMIC);
 	DC_LOGGER_INIT(dc->ctx->logger);
 
 	BW_VAL_TRACE_COUNT();