powerpc/32s: Inline flush_tlb_range() and flush_tlb_kernel_range()

flush_tlb_range() and flush_tlb_kernel_range() are trivial calls to
flush_range().

Make flush_range() global and inline flush_tlb_range()
and flush_tlb_kernel_range().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c7029a78e78709ad9272d7a44260e06b649169b2.1603348103.git.christophe.leroy@csgroup.eu