LU-6245 lnet: Avoid nid range related forward declarations in nidstring.c

LU-6245 lnet: Avoid nid range related forward declarations in nidstring.c

Since forward declarations are frowned on upstream we move
the NID range handling to near the start of the nidstring.c
file.

Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Change-Id: I03961e1f5a89a4bf60873fcc3fc1522542e4931a
Reviewed-on: http://review.whamcloud.com/15086
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>