The "desc" pointer can't possibly be NULL here.  If we can't find the
correct "desc" then tt points to the last element of the
fsl_mc_accepted_cmds[] array.  Fix this by testing if
"i == FSL_MC_NUM_ACCEPTED_CMDS" instead.

Fixes: 2cf1e703 ("bus: fsl-mc: add fsl-mc userspace support")
Acked-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20210208170949.3070898-2-ciorneiioana@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>