arm64: Revert "arm64: kaslr: fix breakage with CONFIG_MODVERSIONS=y"

This reverts commit 9c0e83c3, which
is no longer needed now that the modversions code plays nice with
relocatable PIE kernels.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>