Replace tlb_flush_local() by tlb_flush() as even not global mappings
could be fetched to TLB(s) on other cores by speculative table walk.
From OS point of view, it was not a problem as either such mappings
were not used anymore or they were flushed from TLB(s) when reused.
However, from hardware point of view, it was a problem. Not flushed
mappings could be a target for speculative reads or prefetches (which
might be quite aggresive on ARM cores). As speculative read can fill
cacheline, it can cause a real problem, when physical page is reused,
but mapped with different memory attributes.
Anyhow, it's good to have only valid mappings in TLB(s).
Approved by: kib (mentor)
b09e6b5c6e