Add support for ECDSA P-256 with SHA256

This adds a small EC library that is capable of verifying a signature of
SHA256 with ECDSA on the NIST P-256 curve.

Change-Id: I2a16639c92a77e8e4783c47ffbc56676de56eb59
diff --git a/libmincrypt/tools/Android.mk b/libmincrypt/tools/Android.mk
index b61234a..3154914 100644
--- a/libmincrypt/tools/Android.mk
+++ b/libmincrypt/tools/Android.mk
@@ -13,9 +13,10 @@
 # limitations under the License.
 
 LOCAL_PATH := $(call my-dir)
-include $(CLEAR_VARS)
 
+include $(CLEAR_VARS)
 LOCAL_MODULE := dumpkey
 LOCAL_SRC_FILES := DumpPublicKey.java
 LOCAL_JAR_MANIFEST := DumpPublicKey.mf
+LOCAL_STATIC_JAVA_LIBRARIES := bouncycastle-host
 include $(BUILD_HOST_JAVA_LIBRARY)