Revert "net: fix rds_iovec page count overflow"

Revert "net: fix rds_iovec page count overflow"

This reverts commit bd378dd6df5ca43021a49f72441a6c14d9784bed (originally
commit 1b1f693d7ad6d193862dcb1118540a030c5e761f upstream).

I messed it up in backporting it to the .32-stable kernel, so revert it
for now and try it again the next review cycle.

Cc: Thomas Pollet <thomas.pollet@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Grover <andy.grover@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>