[benchmark] Change the swiftpm pm package to conditional ObjectiveCNoBridgingStubs on Xcode and SWIFT_PACKAGE.

Otherwise while xcrun swift build will work, a generate xcodeproject from
swiftpm will not.

Author: gottesmm

benchmark/utils/main.swift

@@ -92,7 +92,7 @@ import NopDeinit
 import ObjectAllocation
 import ObjectiveCBridging
 import ObjectiveCBridgingStubs
-#if !SWIFT_PACKAGE
+#if !(SWIFT_PACKAGE || Xcode)
 import ObjectiveCNoBridgingStubs
 #endif
 import ObserverClosure
@@ -254,7 +254,7 @@ registerBenchmark(NopDeinit)
 registerBenchmark(ObjectAllocation)
 registerBenchmark(ObjectiveCBridging)
 registerBenchmark(ObjectiveCBridgingStubs)
-#if !SWIFT_PACKAGE
+#if !(SWIFT_PACKAGE || Xcode)
 registerBenchmark(ObjectiveCNoBridgingStubs)
 #endif
 registerBenchmark(ObserverClosure)