drm/amd/display: Check UnboundedRequestEnabled's value

CalculateSwathAndDETConfiguration_params_st's UnboundedRequestEnabled
is a pointer (i.e. dml_bool_t *UnboundedRequestEnabled), and thus
if (p->UnboundedRequestEnabled) checks its address, not bool value.

This fixes 1 REVERSE_INULL issue reported by Coverity.

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>