SLPI: use upstream patches
The upstream patches supersede the downstream patches, see https://lore.kernel.org/linux-remoteproc/20230330164633.117335-1-me@dylanvanassche.be/.
The upstream patches supersede the downstream patches, see https://lore.kernel.org/linux-remoteproc/20230330164633.117335-1-me@dylanvanassche.be/.