[src] Remove redundant/overwritten/deprecated command line argument to generator. (#8008)

These arguments were overwritten by a --ns:ObjCRuntime a few lines later, so
they never had any effect.

src/Makefile

@@ -590,7 +590,6 @@ $(BUILD_DIR)/watchos.rsp: Makefile Makefile.generator frameworks.sources
 		-tmpdir=$(WATCH_BUILD_DIR)/watch                         \
 		-baselib=$(WATCH_BUILD_DIR)/watch/core.dll               \
 		-attributelib=$(WATCH_BUILD_DIR)/Xamarin.WatchOS.BindingAttributes.dll \
-		-ns=MonoTouch.ObjCRuntime                                \
 		-native-exception-marshalling                            \
 		$(WATCH_GENERATED_DEFINES)				\
 		--ns:ObjCRuntime                                         \
@@ -755,7 +754,6 @@ $(BUILD_DIR)/tvos.rsp: Makefile Makefile.generator frameworks.sources
 		-baselib=$(TVOS_BUILD_DIR)/tvos/core.dll               \
 		-attributelib=$(TVOS_BUILD_DIR)/Xamarin.TVOS.BindingAttributes.dll \
 		$(TVOS_GENERATED_DEFINES)				\
-		-ns=MonoTouch.ObjCRuntime                                \
 		-native-exception-marshalling                            \
 		--ns:ObjCRuntime                                         \
 		$(TVOS_APIS)                                            \