uboot-imx

SPL: Limit image name print length

If image name is longer than 32 bytes, then it will be truncated.
This will remove '\0' at the end of the line, so printf will
go out of string limit.

Signed-off-by: Taras Kondratiuk <taras@ti.com>
Reviewed-by: Tom Rini <trini@ti.com>