LU-9859 libcfs: remove cfs_size_round()

LU-9859 libcfs: remove cfs_size_round()

Now that everyone is moved to round_up() we can safely remove the
macro cfs_size_round().

Test-Parameters: trivial
Change-Id: If8e1aff5e89007eeb38c5810c68282d51e37f019
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/51009
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Timothy Day <timday@amazon.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>