board: STiH410-B2260: Set SYS_BOOTM_LEN to 16M

With recent kernel v4.18-rcx, uImage becomes bigger than 8MB.
Set SYS_BOOTM_LEN to 16MB, this fix the following error message:
"Fix Loading Kernel Image ... Image too large: increase
CONFIG_SYS_BOOTM_LEN"

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
1 file changed