usign: update to latest Git HEAD

f34a383 main: fix some resource leaks

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
(cherry picked from commit 81e93fff7d867851f2fedd966a931336d4092686)

package/system/usign/Makefile

@@ -5,9 +5,9 @@ PKG_RELEASE:=1
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL=$(PROJECT_GIT)/usign.git
-PKG_SOURCE_DATE:=2019-08-06
-PKG_SOURCE_VERSION:=5a52b379902471cef495687547c7b568142f66d2
-PKG_MIRROR_HASH:=9779f6d6718a7f7cd3e28aa7feefc9b3f4b0c7a85cb58ff18afbeb6b4372177a
+PKG_SOURCE_DATE:=2019-09-21
+PKG_SOURCE_VERSION:=f34a383eeed6282fa16fb021157a60c75f33fdcd
+PKG_MIRROR_HASH:=74dc05f3ff24995193956a2803d20994fa6fce3d9e7d997002ee524618fbcec6
 CMAKE_INSTALL:=1
 PKG_CHECK_FORMAT_SECURITY:=1
 PKG_USE_MIPS16:=0