thermal: Remove COMPILE_TEST for IMX_SC_THERMAL

i.MX SCU thermal driver depends on IMX_SCU which does NOT have
COMPILE_TEST enabled, so need to remove COMPILE_TEST for i.MX
SCU thermal as well.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1583222684-10229-2-git-send-email-Anson.Huang@nxp.com