arm64/numa: Unify common error path in numa_init()

At present numa_free_distance() is being called before numa_distance is
even initialized with numa_alloc_distance() which is really pointless.
Instead lets call numa_free_distance() on the common error path inside
numa_init() after numa_alloc_distance() has been successful.

Fixes: 1a2db300

 ("arm64, numa: Add NUMA support for arm64 platforms")
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>