arm64: Kconfig: remove redundant HAVE_ARCH_TRANSPARENT_HUGEPAGE definition

HAVE_ARCH_TRANSPARENT_HUGEPAGE has been defined in arch/Kconfig already,
the ARM64 version is identical with it and the default value is Y. So remove
the redundant definition and just select it under CONFIG_ARM64.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
[will: sort into alphabetical order whilst I'm resolving conflicts]
Signed-off-by: Will Deacon <will.deacon@arm.com>