arm64: dts: exynos: Fix silent hang after boot on Espresso

arm64: dts: exynos: Fix silent hang after boot on Espresso

[ Upstream commit b072714bfc0e42c984b8fd6e069f3ca17de8137a ]

Once regulators are disabled after kernel boot, on Espresso board silent
hang observed because of LDO7 being disabled.  LDO7 actually provide
power to CPU cores and non-cpu blocks circuitries.  Keep this regulator
always-on to fix this hang.

Fixes: 9589f7721e16 ("arm64: dts: Add S2MPS15 PMIC node on exynos7-espresso")
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>