Code cleanup for nfs4 utilities:

• Mark internal routines as static;
• Eliminate unused parameters where possible, mark __unused for others;
• Remove unused variables;
• Use %jd for int64_t values in printf();
• Add appropriate %d for printf to match its parameter;
• Rename a variable to resolve conflict with revoke(2);

Reviewed by: rmacklem
Tested with: make universe (bugs are mine)