arm64: tlb: Remove redundant !CONFIG_HAVE_RCU_TABLE_FREE code

mainline inclusion
from mainline-4.20-rc1
commit: 07212cd4
category: feature
feature: Reduce synchronous TLB invalidation on ARM64
bugzilla: NA
CVE: NA

--------------------------------------------------

If there's one thing the RCU-based table freeing doesn't need, it's more
ifdeffery.

Remove the redundant !CONFIG_HAVE_RCU_TABLE_FREE code, since this option
is unconditionally selected in our Kconfig.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Xuefeng Wang <wxf.wang@hisilicon.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>