thermal: Fix build error of missing devm_ioremap_resource on UM

The devres.o gets linked if HAS_IOMEM is present so on ARCH=um
allyesconfig (COMPILE_TEST) failed on many files with:

drivers/built-in.o: In function `kirkwood_thermal_probe':
kirkwood_thermal.c:(.text+0x390a25): undefined reference to `devm_ioremap_resource'
drivers/built-in.o: In function `exynos_tmu_probe':
exynos_tmu.c:(.text+0x39246b): undefined reference to `devm_ioremap'

The users of devm_ioremap_resource() which are compile-testable should
depend on HAS_IOMEM.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>