Do not build jemalloc with clang.

Temporarily disable clang build since it fails on arm64 and mips.

Change-Id: I2a51b67c4b8985a774a60c919a13a71e08bcb074
diff --git a/Android.mk b/Android.mk
index d1e2638..7c6fa2f 100644
--- a/Android.mk
+++ b/Android.mk
@@ -79,6 +79,10 @@
 #-----------------------------------------------------------------------
 include $(CLEAR_VARS)
 
+# Temporarily disable clang build for this project:
+#   mips and arm64 do not compile with clang
+LOCAL_CLANG := false
+
 LOCAL_MODULE := libjemalloc
 LOCAL_MODULE_TAGS := optional