Fix compile error in gogs

Dockerfile

@@ -13,7 +13,7 @@ RUN mkdir -p ${GOPATH}/src/github.com/gogits && \
     cd ${GOPATH}/src/github.com/gogits && \
     git clone https://github.com/gogits/gogs.git && \
     cd gogs && \
-    git reset --hard 47ac579f092cef9128fa0c74798ecaffa2c888f9 && \
+    git reset --hard 54b52de6eed4eb2f76620c48189ba3167c290121 && \
     go get ./... && \
     go build && \
     go install && \