Convert CONFIG_ARMV8_SWITCH_TO_EL1 to Kconfig

This converts the following to Kconfig:
   CONFIG_ARMV8_SWITCH_TO_EL1

Cc: Alex Nemirovsky <alex.nemirovsky@cortina-access.com>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Cc: Tien Fong Chee <tien.fong.chee@intel.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/arch/arm/cpu/armv8/Kconfig b/arch/arm/cpu/armv8/Kconfig
index 9967376..4d4469c 100644
--- a/arch/arm/cpu/armv8/Kconfig
+++ b/arch/arm/cpu/armv8/Kconfig
@@ -31,6 +31,12 @@
 	  it can be safely enabled when EL2/EL3 initialized SMPEN bit
 	  or when CPU implementation doesn't include that register.
 
+config ARMV8_SWITCH_TO_EL1
+	bool "Enable switching to running in EL1"
+	help
+	  In some circumstances we need to switch to running in EL1.
+	  Enable this option to have U-Boot switch to EL1.
+
 config ARMV8_SPIN_TABLE
 	bool "Support spin-table enable method"
 	depends on ARMV8_MULTIENTRY && OF_LIBFDT