Fix sim-eng build.

Exclude crespo files from sim-eng build.  Some of the makefiles depend
explicitly on libc (which is weird) and libdl (which is normal for us),
and neither of those plays well in sim-eng.

Change-Id: I2907a04ddb274597f75fdafacff99df8bb005168
diff --git a/Android.mk b/Android.mk
index d0ef6e4..dbef347 100644
--- a/Android.mk
+++ b/Android.mk
@@ -35,4 +35,6 @@
 
 endif
 
+ifneq ($(TARGET_SIMULATOR),true)
 include $(call all-makefiles-under,$(LOCAL_PATH))
+endif