uclient: update to 19.07 Git HEAD

51e16eb uclient-fetch: add option to read POST data from file
99aebe3 uclient: Add string error function

Fixes: 0c910d8459 ("uclient: Update to version 2020-06-17")
Signed-off-by: Jo-Philipp Wich <jo@mein.io>

package/libs/uclient/Makefile

@@ -5,9 +5,9 @@ PKG_RELEASE=1
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL=$(PROJECT_GIT)/project/uclient.git
-PKG_MIRROR_HASH:=b1127b28f98c9b45e046a76086b281b35c094fad1dc511ce0af095b733c86359
-PKG_SOURCE_DATE:=2019-05-30
-PKG_SOURCE_VERSION:=3b3e368dead01979e985cb167873fe9868b15d19
+PKG_MIRROR_HASH:=09857c0463c9ff56ae37fff4a73f58008ea2d844c909aab6669277afa8ef1e72
+PKG_SOURCE_DATE:=2020-06-17
+PKG_SOURCE_VERSION:=51e16ebffc740c6afcdd45aced20fc0354a502d7
 CMAKE_INSTALL:=1
 
 PKG_BUILD_DEPENDS:=ustream-ssl