arch/riscv: Instead of use Kconfig items to compiler flags. [1/1]

PD#SWPL-68240

Problem:
Refactor for all.

Solution:
Instead of use Kconfig items to compiler flags.

Verify:
N/A

Change-Id: Idba46a2f2c3fc90c4419ea3190f692c1c72c9cf9
Signed-off-by: Xiaohu.Huang <xiaohu.huang@amlogic.com>
6 files changed