LU-5552 llite: make sure we do cl_page_clip on the last page

When we are doing a partial IO on both first and last page,
the logic currently only call cl_page_clip on the first page, which
will end up with a incorrect i_size.

Signed-off-by: Li Dongyang <dongyang.li@anu.edu.au>
Change-Id: Ia7be3d71e535d583cb424bb816c14015d3141cdb
Reviewed-on: http://review.whamcloud.com/11630
Reviewed-by: Ian Costello <costello.ian@gmail.com>
Tested-by: Jenkins
Reviewed-by: Niu Yawei <yawei.niu@intel.com>
Reviewed-by: Li Xi <pkuelelixi@gmail.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>