LU-4669 lmv: remove unused lmv_adjust_dirpages()

LU-4669 lmv: remove unused lmv_adjust_dirpages()

This patch fixes the following compile error by removing the
dead codes: "error: 'lmv_adjust_dirpages' defined but not used".
This code was moved to mdc_adjust_dirpages() in commit 4e0c8aeb94
(http://review.whamcloud.com/7043).

Signed-off-by: Jian Yu <jian.yu@intel.com>
Change-Id: I0cc7dbb5aad50727cc4d5cc36cce964a236077a3
Reviewed-on: http://review.whamcloud.com/9810
Tested-by: Jenkins
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>