ARM: Clean up CONFIG_ARMV7_NONSEC/VIRT/PSCI conditions

ARM: Clean up CONFIG_ARMV7_NONSEC/VIRT/PSCI conditions

CONFIG_ARMV7_VIRT depends on CONFIG_ARMV7_NONSEC, thus doesn't need to
be taken into account additionally. CONFIG_ARMV7_PSCI is only set on
boards that support CONFIG_ARMV7_NONSEC, and it only works on those.

CC: Tang Yuantian <[email protected]>
CC: York Sun <[email protected]>
CC: Steve Rae <[email protected]>
CC: Andre Przywara <[email protected]>
Signed-off-by: Jan Kiszka <[email protected]>
Tested-by: Alison Wang <[email protected]>
Signed-off-by: Tom Warren <[email protected]>