ustream-ssl: update to latest git HEAD

527e700 ustream-ssl: Remove RC4 from ciphersuite in server mode.
39a6ce2 ustream-ssl: Enable ECDHE with OpenSSL.
45ac930 remove polarssl support

Signed-off-by: John Crispin <john@phrozen.org>

package/libs/ustream-ssl/Makefile

@@ -5,9 +5,9 @@ PKG_RELEASE:=3
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL=$(PROJECT_GIT)/project/ustream-ssl.git
-PKG_SOURCE_DATE:=2016-07-02
-PKG_SOURCE_VERSION:=ec80adaa1b47f28d426fa19c692011ce60b992d6
-PKG_MIRROR_HASH:=bfbad6b4e8c1e933f0bfaab43cbdd44a536c08128c3a779e6f2395a6a886aab7
+PKG_SOURCE_DATE:=2018-04-30
+PKG_SOURCE_VERSION:=527e7002d0429465bd49c0c0d416ef22fbf5ae86
+PKG_MIRROR_HASH:=b0b4219730a369741a192a67d4fbf7328bd62df8ae4f0d0e3084461e3bbaba54
 CMAKE_INSTALL:=1
 
 PKG_BUILD_DIR=$(BUILD_DIR)/$(PKG_NAME)-$(BUILD_VARIANT)/$(PKG_SOURCE_SUBDIR)