Similar to the lzma-loader on our MIPS targets, the spi-loader acts as
a second-stage loader that will then load and start the actual kernel.
As the TL-WDR4900 uses SPI-NOR and the P1010 family does not have support
for memory mapping of this type of flash, this loader needs to contain a
basic driver for the FSL ESPI controller.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
(cherry picked from commit a296055b82fbb20457273492069ce9d62009e2a1)
f7a43e4606