[interop][SwiftToCxx] NFC, use elif defined instead of elifdef for _SwiftStdlibCxxOverlay.h

hyp · hyp · commit c77249c38d65 · 2022-12-14T16:36:13.000-08:00
diff --git a/lib/PrintAsClang/_SwiftStdlibCxxOverlay.h b/lib/PrintAsClang/_SwiftStdlibCxxOverlay.h
@@ -31,7 +31,7 @@ SWIFT_INLINE_THUNK T_0_0 get() const
 
 #undef SWIFT_CXX_INTEROP_OPTIONAL_MIXIN
 
-#elifdef SWIFT_CXX_INTEROP_STRING_MIXIN
+#elif defined(SWIFT_CXX_INTEROP_STRING_MIXIN)
 
 #ifndef SWIFT_CXX_INTEROP_HIDE_STL_OVERLAY
 
