arm64: mm: fix resume for 52-bit enabled builds

__cpu_setup() was changed to take the actual number of VA bits in x0,
however the resume path was not updated at the same time.

Load `vabits_actual` in the resume path, to ensure that the correct
number of VA bits is used.

This fixes booting v6.0-rc kernels on my Juno.

Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Fixes: 0aaa6853

 ("arm64: mm: fix booting with 52-bit address space")
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20220909124311.38489-1-joey.gouly@arm.com
Signed-off-by: Will Deacon <will@kernel.org>