openaes data encryption: turn off by default

Until the code can be removed, we will turn off openaes encryption
of data files by default. There are many restore issues that are
caused with openaes enabled. For maintainers who want to enable it
set TW_EXCLUDE_ENCRYPTED_BACKUPS := false on BoardConfig.

Change-Id: Ie284b03c7cc4c77a0a9dbcc460817fe3fe08b839
diff --git a/Android.mk b/Android.mk
index 9f7c022..10d2894 100755
--- a/Android.mk
+++ b/Android.mk
@@ -336,7 +336,7 @@
 ifneq ($(TW_CUSTOM_CPU_TEMP_PATH),)
 	LOCAL_CFLAGS += -DTW_CUSTOM_CPU_TEMP_PATH=$(TW_CUSTOM_CPU_TEMP_PATH)
 endif
-ifneq ($(TW_EXCLUDE_ENCRYPTED_BACKUPS), true)
+ifneq ($(TW_EXCLUDE_ENCRYPTED_BACKUPS),)
     LOCAL_SHARED_LIBRARIES += libopenaes
 else
     LOCAL_CFLAGS += -DTW_EXCLUDE_ENCRYPTED_BACKUPS