LU-6142 lustre: make various 'struct file_operations' static

LU-6142 lustre: make various 'struct file_operations' static

These 'struct file_operations' are only used locally, so make them
static.
Except lprocfs_evict_client_fops() which isn't used at all and doesn't
exist, so discard the declaration.

Test-Parameters: trivial
Signed-off-by: Mr NeilBrown <neilb@suse.de>
Change-Id: Ib6c51683c1e765db202b3f72d2accebe17191303
Reviewed-on: https://review.whamcloud.com/39741
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>