Update QGCExternalLibs.pri

QGCExternalLibs.pri

@@ -254,6 +254,7 @@ contains (DEFINES, DISABLE_AIRMAP) {
             rm -rf $${AIRMAP_PLATFORM_SDK_PATH} && \
             mkdir -p "$${AIRMAP_PLATFORM_SDK_PATH}/linux/$${AIRMAP_QT_PATH}" && \
             mkdir -p "$${AIRMAP_PLATFORM_SDK_PATH}/include/airmap" && \
+            mkdir -p "$${AIRMAP_PLATFORM_SDK_PATH}/$${AIRMAP_PLATFORM_SDK_INSTALL_DIR}" && \
             wget -q -O "$${OUT_PWD}/$${AIRMAP_PLATFORM_SDK_FILENAME}" "$${AIRMAP_PLATFORM_SDK_URL}" && \
             ar p "$${AIRMAP_PLATFORM_SDK_FILENAME}" data.tar.gz | tar xvz -C "$${AIRMAP_PLATFORM_SDK_PATH}/" --strip-components=1 && \
             mv -u "$${AIRMAP_PLATFORM_SDK_PATH}/$${AIRMAP_PLATFORM_SDK_INSTALL_DIR}/usr/lib/x86_64-linux-gnu/*" "$${AIRMAP_PLATFORM_SDK_PATH}/linux/$${AIRMAP_QT_PATH}/" && \