arch/riscv: add license. [1/1]

PD#SWPL-69730

Problem:
add license

Solution:
add license

Verify:
ad401_a113l

Signed-off-by: yang.li <yang.li@amlogic.com>
Change-Id: Ie1732fb2c035ef0d7435d9bc4eaf8df125f2f808
9 files changed