thermal: exynos: Disable the regulator on probe failure

During probe the regulator (if present) was enabled but not disabled in
case of failure. So an unsuccessful probe lead to enabling the
regulator which was actually not needed because the device was not
enabled.

Additionally each deferred probe lead to increase of regulator enable
count so it would not be effectively disabled during removal of the
device.

Test HW: Exynos4412 - Trats2 board

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: 498d22f6 ("thermal: exynos: Support for TMU regulator defined at device tree")
Cc: <stable@vger.kernel.org>
Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Tested-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>