staging: lustre: lprocfs: move lprocfs_stats_[un]lock to a source file

When compiling the kernel without optimization, when using GCOV,
the lprocfs_stats_alloc_one() symbol is not properly exported to
other modules and causes the ptlrpc module to fail loading with
an unknown symbol. There is no reason to export the function
lprocfs_stats_alloc_one. The reason is due to the functions
lprocfs_stats_[un]lock being inline functions in a header file.
Lets untangle this mess and turn those inline functions
into real functions in a source file.

Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8836
Reviewed-on: https://review.whamcloud.com/23773


Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>