Add support for the SPL_BINARY variable to handle sub directories. In
some cases the SPL binary that needs to be deployed is only built to the
spl/ directory in U-Boot. So that a sub directory can be specified in
the SPL_BINARY variable, handle the case so that the deploy code uses
the basename of the path specified in SPL_BINARY.
Signed-off-by: Nathan Rossi <nathan@nathanrossi.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
