Fix syntax error in recent CMake change.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@280042 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CMakeLists.txt

@@ -106,7 +106,7 @@ if ( APPLE AND (LIBCXX_CXX_ABI_LIBNAME STREQUAL "libcxxabi" OR
       "/usr/lib/libSystem.B.dylib")
   else()
     if (DEFINED CMAKE_OSX_SYSROOT)
-      list(FIND ${CMAKE_OSX_ARCHITECTURES} "armv7" OSX_HAS_ARMV7)
+      list(FIND CMAKE_OSX_ARCHITECTURES "armv7" OSX_HAS_ARMV7)
       if (NOT OSX_HAS_ARMV7 EQUAL -1)
         set(OSX_RE_EXPORT_LINE
           "${CMAKE_OSX_SYSROOT}/usr/lib/libc++abi.dylib"