powerpc/64s: Kill the unused argument of exit_lazy_flush_tlb

powerpc/64s: Kill the unused argument of exit_lazy_flush_tlb

In previous patch we removed the only caller of exit_lazy_flush_tlb()
which was passing always_flush = false in it's second argument.

With that gone, all the callers of exit_lazy_flush_tlb() are local to
radix_pgtable.c and there is no need of an additional argument.

This patch does the required cleanup. There should not be any
functionality change in this patch.

Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/6f96ea53588034312ae84f74b1e2fa9c4ce7cfd5.1773078178.git.ritesh.list@gmail.com