LU-14976 ptlrpc: align function names with param names

LU-14976 ptlrpc: align function names with param names

Change the internal function names for the ptlrpc proc tunables
to match the parameter names exposed to userspace.  Otherwise it
is needlessly complex to find the function that implements the
"nrs_policies" parameter, since the parameter use itself is wrapped
in a macro that generates the proc handling structure.

Clean up code style in related functions.

Test-Parameters: trivial
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: I9079766cccade963f1510cfcce228da9be3ebbe5
Reviewed-on: https://review.whamcloud.com/44817
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>