[test] Make sure to use the mock SDK overlays for these IRGen tests

And disable them on non-ObjC platforms again, because those overlays
depend on a stdlib that contains _ObjectiveCBridgeable.

Author: jrose-apple

test/IRGen/clang_inline.swift

@@ -1,11 +1,13 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-swift-frontend -enable-objc-interop -assume-parsing-unqualified-ownership-sil -sdk %S/Inputs -primary-file %s -O -disable-sil-perf-optzns -disable-llvm-optzns -emit-ir -Xcc -fstack-protector | %FileCheck %s
+// RUN: %build-irgen-test-overlays
+// RUN: %target-swift-frontend -enable-objc-interop -assume-parsing-unqualified-ownership-sil -sdk %S/Inputs -primary-file %s -O -disable-sil-perf-optzns -disable-llvm-optzns -emit-ir -Xcc -fstack-protector -I %t | %FileCheck %s
 
 // RUN: %empty-directory(%t/Empty.framework/Modules/Empty.swiftmodule)
-// RUN: %target-swift-frontend -assume-parsing-unqualified-ownership-sil -emit-module-path %t/Empty.framework/Modules/Empty.swiftmodule/%target-swiftmodule-name %S/../Inputs/empty.swift -module-name Empty
-// RUN: %target-swift-frontend -assume-parsing-unqualified-ownership-sil -sdk %S/Inputs -primary-file %s -F %t -DIMPORT_EMPTY -O -disable-sil-perf-optzns -disable-llvm-optzns -emit-ir -Xcc -fstack-protector -enable-objc-interop | %FileCheck %s
+// RUN: %target-swift-frontend -assume-parsing-unqualified-ownership-sil -emit-module-path %t/Empty.framework/Modules/Empty.swiftmodule/%target-swiftmodule-name %S/../Inputs/empty.swift -module-name Empty -I %t
+// RUN: %target-swift-frontend -assume-parsing-unqualified-ownership-sil -sdk %S/Inputs -primary-file %s -I %t -F %t -DIMPORT_EMPTY -O -disable-sil-perf-optzns -disable-llvm-optzns -emit-ir -Xcc -fstack-protector -enable-objc-interop | %FileCheck %s
 
 // REQUIRES: CPU=i386 || CPU=x86_64
+// REQUIRES: objc_interop
 
 #if IMPORT_EMPTY
   import Empty

test/IRGen/clang_inline_reverse.swift

@@ -1,8 +1,11 @@
 // Same test as clang_inline.swift, but with the order swapped.
 
-// RUN: %target-swift-frontend -assume-parsing-unqualified-ownership-sil -sdk %S/Inputs -primary-file %s -enable-objc-interop -emit-ir -module-name clang_inline | %FileCheck %s
+// RUN: %empty-directory(%t)
+// RUN: %build-irgen-test-overlays
+// RUN: %target-swift-frontend -assume-parsing-unqualified-ownership-sil -sdk %S/Inputs -primary-file %s -enable-objc-interop -emit-ir -module-name clang_inline -I %t | %FileCheck %s
 
 // REQUIRES: CPU=i386 || CPU=x86_64
+// REQUIRES: objc_interop
 
 import gizmo
 

test/IRGen/objc_block_storage.sil

@@ -1,6 +1,9 @@
-// RUN: %target-swift-frontend -assume-parsing-unqualified-ownership-sil -gnone -enable-objc-interop -sdk %S/Inputs %s -emit-ir | %FileCheck %s
+// RUN: %empty-directory(%t)
+// RUN: %build-irgen-test-overlays
+// RUN: %target-swift-frontend -assume-parsing-unqualified-ownership-sil -gnone -enable-objc-interop -sdk %S/Inputs -I %t %s -emit-ir | %FileCheck %s
 
 // REQUIRES: CPU=x86_64
+// REQUIRES: objc_interop
 
 sil_stage canonical