net: stmmac: dwmac-intel-plat: remove config data on error

commit 3765d86f upstream.

Remove the config data when rate setting fails.

Fixes: 9efc9b2b ("net: stmmac: Add dwmac-intel-plat for GBE driver")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Link: https://lore.kernel.org/r/20210120110745.36412-1-bianpan2016@163.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>