BUG 808328 - xfs_support EXPORTs symbols with generic names

[pv@xxxxxxxxxxxxx (dxm@xxxxxxxxxxxx)]

View Incident: 
http://co-op.engr.sgi.com/BugWorks/code/bwxquery.cgi?search=Search&wlong=1&view_type=Bug&wi=808328

Submitter : dxm                       Submitter Domain : engr               
Assigned Engineer : dxm               Assigned Domain : engr                
Assigned Group : xfs-linux            Category : software                   
Customer Reported : F                 Priority : 4                          
Project : xfs-linux                   Status : open                         
Description :
xfs_support uses EXPORT_SYMBOL to export a bunch of symbols
into the kernel global symbol namespace. Some of the symbol
names are quite generic and hence potentially clash with other
exports.

Case in point is "copyin" and "copyout".

we can:
        - move code back into XFS
        - make simple functions static inline
        - prefix symbols and use macro aliasing to avoid
                changing all references to them
        - prefix symbols and change all references