Fix -vet complaints in `core:sys/darwin/Foundation`

core/sys/darwin/Foundation/NSMenuItem.odin

@@ -2,7 +2,6 @@ package objc_Foundation
 
 import "base:builtin"
 import "base:intrinsics"
-import "core:c"
 
 KeyEquivalentModifierFlag :: EventModifierFlag
 KeyEquivalentModifierMask :: EventModifierFlags

core/sys/darwin/Foundation/objc_helper.odin

@@ -79,7 +79,6 @@ register_subclass :: proc(
 
 	objc_registerClassPair(cls)
 	meta_cls    := class_get_metaclass(cls)
-	class_size1 := uint(class_getInstanceSize(cls))
 	meta_size   := uint(class_getInstanceSize(meta_cls))
 
 	// Offsets are always aligned to 8-byte boundary