spdlog checkout master branch is no more the default (additional branch)

build/scripts/build_helper.spgw

@@ -95,6 +95,7 @@ install_spdlog_from_git() {
     fi
 
     git clone $GIT_URL
+    cd spdlog && git checkout master
     ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
     popd
   fi