clk: mediatek: Get regmap without syscon compatible check

clk: mediatek: Get regmap without syscon compatible check

Not all clock providers need to be marked compatible with "syscon"
for system configuration usage, so use device_node_to_regmap() to
skip "syscon" check.

Signed-off-by: Chun-Jie Chen <chun-jie.chen@mediatek.com>
Link: https://lore.kernel.org/r/20210726105719.15793-6-chun-jie.chen@mediatek.com
Reviewed-by: Ikjoon Jang <ikjn@chromium.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>