Commit a6335fa1 fixed the case with gap between initrd and next usable PFN zone,
but broken the case when initrd is combined with usable memory into one region
(in add_memory_region()). Restore the fixup initially brought in by f9a7febd

.

---- error message ----
Unpacking initramfs...
Initramfs unpacking failed: junk in compressed archive
BUG: Bad page state in process swapper  pfn:00261
page:81004c20 count:0 mapcount:-127 mapping:  (null) index:0x2
flags: 0x0()
page dumped because: nonzero mapcount
CPU: 0 PID: 1 Comm: swapper Not tainted 4.2.0+ #1782
-----------------------

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Reported-by: Tony Wu <tung7970@gmail.com>
Tested-by: Tony Wu <tung7970@gmail.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Joe Perches <joe@perches.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11086/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>