lib: utils: Add FDT parsing API common for both ACLINT and CLINT

We add fdt_parse_aclint_node() which can parse both ACLINT and
CLINT DT nodes. This means fdt_parse_clint_node() is not required
anymore so we remove it as well.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>