powerpc: P1010RDB: Rework local command to not be included in SPL

Add a CONFIG_SPL_BUILD guard around the code for the "mux" command so
it is not included in SPL.

Cc: Qiang Zhao <qiang.zhao@nxp.com>
Cc: York Sun <york.sun@nxp.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: York Sun <york.sun@nxp.com>
Reviewed-by: Qiang Zhao <qiang.zhao@nxp.com>
1 file changed