include: Add function prototype for crypto init

Add function prototype to appropriate header file in order to
avoid compilation warning. It is done in an effort to enable
WERROR.

Change-Id: Id355093c022f17dc3f0592008d786d2b27e5466d
diff --git a/include/target.h b/include/target.h
index 055634b..055fdb7 100644
--- a/include/target.h
+++ b/include/target.h
@@ -83,4 +83,5 @@
 bool target_use_signed_kernel(void);
 int _emmc_recovery_init(void);
 void ulpi_write(unsigned val, unsigned reg);
+void target_crypto_init_params(void);
 #endif