[XLA:GPU] Cleanup dead ExecTimeOptimizationEffort.

PiperOrigin-RevId: 708338000

xla/service/gpu/flag_utils.h

@@ -25,12 +25,6 @@ limitations under the License.
 namespace xla {
 namespace gpu {
 
-// Returns compile time optimization effort in range [-1.0, 1.0] where values <
-// 0.0 indicate skipping passes which might optimize the final runtime (thus
-// improving compile time), and values > 0.0 indicate running additional passes
-// which may improve runtime at the cost of compilation time.
-float ExecTimeOptimizationEffort(const HloModuleConfig& config);
-
 // Defines the optimization effort to trigger additional passes which optimize
 // communication compute overlap.
 constexpr float kExtraCollectiveOptimizations = 0.2;