Module interfaces: preserve -autolink-force-load (#24262)

Otherwise the overlays won't be force-loaded when you import them.

(This feature could possibly be scoped back at this point, but it's
not something that should be changed just by using module interfaces!)

(cherry picked from commit 9b2db03)

Author: jrose-apple

include/swift/Option/Options.td

@@ -321,7 +321,7 @@ def module_link_name : Separate<["-"], "module-link-name">,
 def module_link_name_EQ : Joined<["-"], "module-link-name=">,
   Flags<[FrontendOption]>, Alias<module_link_name>;
 def autolink_force_load : Flag<["-"], "autolink-force-load">,
-  Flags<[FrontendOption, HelpHidden]>,
+  Flags<[FrontendOption, ModuleInterfaceOption, HelpHidden]>,
   HelpText<"Force ld to link against this module even if no symbols are used">;
 
 def emit_module : Flag<["-"], "emit-module">,

test/ParseableInterface/option-preservation.swift

@@ -1,20 +1,22 @@
 // RUN: %empty-directory(%t)
 
-// RUN: %target-swift-frontend -enable-library-evolution -emit-parseable-module-interface-path %t.swiftinterface -module-name t %s -emit-module -o /dev/null -Onone -enforce-exclusivity=unchecked
+// RUN: %target-swift-frontend -enable-library-evolution -emit-parseable-module-interface-path %t.swiftinterface -module-name t %s -emit-module -o /dev/null -Onone -enforce-exclusivity=unchecked -autolink-force-load
 // RUN: %FileCheck %s < %t.swiftinterface -check-prefix=CHECK-SWIFTINTERFACE
 //
 // CHECK-SWIFTINTERFACE: swift-module-flags:
 // CHECK-SWIFTINTERFACE-SAME: -enable-library-evolution
 // CHECK-SWIFTINTERFACE-SAME: -Onone
 // CHECK-SWIFTINTERFACE-SAME: -enforce-exclusivity=unchecked
+// CHECK-SWIFTINTERFACE-SAME: -autolink-force-load
 
 // Make sure flags show up when filelists are enabled
 
-// RUN: %target-build-swift %s -driver-filelist-threshold=0 -emit-parseable-module-interface -o %t/foo -module-name foo -module-link-name fooCore -force-single-frontend-invocation -Ounchecked -enforce-exclusivity=unchecked 2>&1
+// RUN: %target-build-swift %s -driver-filelist-threshold=0 -emit-parseable-module-interface -o %t/foo -module-name foo -module-link-name fooCore -force-single-frontend-invocation -Ounchecked -enforce-exclusivity=unchecked -autolink-force-load 2>&1
 // RUN: %FileCheck %s < %t/foo.swiftinterface --check-prefix CHECK-FILELIST-INTERFACE
 
 // CHECK-FILELIST-INTERFACE: swift-module-flags:
 // CHECK-FILELIST-INTERFACE-SAME: -target
+// CHECK-FILELIST-INTERFACE-SAME: -autolink-force-load
 // CHECK-FILELIST-INTERFACE-SAME: -module-link-name fooCore
 // CHECK-FILELIST-INTERFACE-SAME: -enforce-exclusivity=unchecked
 // CHECK-FILELIST-INTERFACE-SAME: -Ounchecked