Revert "Try again to fix clang build."

Bug: http://b/20065774
This reverts commit dffd3c58389103d6ee712fac6544217c00c1f315.

Change-Id: I5dd095ff4ab133baa2afcbd4c79fbee55d05c459
(cherry picked from commit f920f821e27c845d2de54c1c92c3ab74587ed31a)
diff --git a/libc/arch-arm64/bionic/libgcc_compat.c b/libc/arch-arm64/bionic/libgcc_compat.c
index 2dae3f5..904cc16 100644
--- a/libc/arch-arm64/bionic/libgcc_compat.c
+++ b/libc/arch-arm64/bionic/libgcc_compat.c
@@ -1,6 +1,6 @@
 /* STOPSHIP: remove this once the flounder blobs have been rebuilt (http://b/20065774). */
 
-#if !defined(__clang__)
+#if defined(__clang__)
 
 extern void __clear_cache(char*, char*);
 extern char _Unwind_Backtrace;