Remove redundant YYLOC global declaration
Cherry picked from https://github.com/u-boot/u-boot/commit/018921ee79d3f30893614b3b2b63b588d8544f73 to fix building with GCC 10
Due to an influx of spam, we have had to impose restrictions on new accounts. Please see this wiki page for instructions on how to get full permissions. Sorry for the inconvenience.
Cherry picked from https://github.com/u-boot/u-boot/commit/018921ee79d3f30893614b3b2b63b588d8544f73 to fix building with GCC 10