Patch series "eldie generated code for folded p4d/pud".

This series elides extraneous generate code for folded p4d/pud.  This came
up when trying to remove __ARCH_USE_5LEVEL_HACK from ARC port.  The code
saving are not a while lot, but still worthwhile IMHO.

bloat-o-meter2 vmlinux-A-baseline vmlinux-E-elide-p?d_clear_bad
add/remove: 0/2 grow/shrink: 0/1 up/down: 0/-146 (-146)
function                                     old     new   delta
p4d_clear_bad                                  2       -      -2
pud_clear_bad                                 20       -     -20
free_pgd_range                               546     422    -124
Total: Before=4137148, After=4137002, chg -1.000000%

This patch (of 3):

Stub out pud_free_tlb() if __PAGETABLE_PUD_FOLDED, independent of
__ARCH_HAS_4LEVEL_HACK

This came up when removing __ARCH_HAS_5LEVEL_HACK for ARC as code bloat
from pud_free_tlb() despite pud being folded (with 2 levels on ARC)

| bloat-o-meter2 vmlinux-B-elide-ARCH_USE_5LEVEL_HACK vmlinux-C-elide-pud=
_free_tlb
| add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-104 (-104)
| function                                     old     new   delta
| free_pgd_range                               656     552    -104
| Total: Before=3D4137276, After=3D4137172, chg -1.000000%

Link: http://lkml.kernel.org/r/20191009222658.961-2-vgupta@synopsys.com


Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Will Deacon <will@kernel.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>