LU-9325 obd: replace lprocfs_str_to_s64

LU-9325 obd: replace lprocfs_str_to_s64

The original goal of lprocfs_str_to_s64[_with_units] was to allow
passing in values of different unit sizes i.e 64K to a proc file.
Their are a few problems with the implementation that prevents its
direct use with sysfs/debugfs. The first problem is that
lprocfs_str_to_s64() was used for a lot of cases where it doesn't
make sense to use it. Often it was used for bool values passing
in or after retrieving a value as signed 64 bit it ensures its in
range of some other unit size. For these cases we can simply move
to kstrtoXXX_from_user(). To handle the case of bool values we
add in supoort for kstrtobool_from_user().

Replace the lprocfs_rd_uint() and lprocfs_wr_uint() generic callbacks
with a simpler, more direct implementation of ldlm_rw_uint_fops.

There's a slight change in lustre debugfs write semantics: Using kstrtox
causes EINVAL when the written number is followed by other (garbage)
characters, whereas previously the garbage would be ignored and such a
write would succeed.

Linux-commit: 8b23093269c84b0da1201e1949c91d0beb9892ef

Change-Id: I39f0ba3dc72685fe6e29c7077f37ad4e69a20b4a
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Signed-off-by: Mathias Rav <mathiasrav@gmail.com>
Reviewed-on: https://review.whamcloud.com/30539
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Ben Evans <bevans@cray.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>