Avoid leak. Free before resetting.

llvm-svn: 269724
diff --git a/compiler-rt/lib/profile/InstrProfilingWriter.c b/compiler-rt/lib/profile/InstrProfilingWriter.c
index 3e90b1d..95f37e8 100644
--- a/compiler-rt/lib/profile/InstrProfilingWriter.c
+++ b/compiler-rt/lib/profile/InstrProfilingWriter.c
@@ -67,9 +67,9 @@
 
 COMPILER_RT_VISIBILITY void lprofDeleteBufferIO(ProfBufferIO *BufferIO) {
   if (DynamicBufferIOBuffer) {
+    FreeHook(DynamicBufferIOBuffer);
     DynamicBufferIOBuffer = 0;
     VPBufferSize = 0;
-    FreeHook(DynamicBufferIOBuffer);
   }
 }