fix: cleanup a logically incorrect && ... || shell sequence

If one of the other &&s had failed other than the last one, we'd have
descended into the OR here.

openwrt-builder-commit.dockerfile

@@ -9,9 +9,7 @@ ARG commit="master"
 RUN cd ${openwrt_dir} \
     && ( git remote add ${remote} ${remoteurl} --tags || true )
 
-RUN cd ${openwrt_dir} \
-    && git fetch --all \
-    && git checkout ${remote}/${commit} || git checkout "${commit}"
+RUN cd ${openwrt_dir} && git fetch --all && { git checkout ${remote}/${commit} || git checkout "${commit}" ; }
 
 RUN cd ${openwrt_dir} \
     && ./scripts/feeds update -a \