kernel-doc: fix new warnings in auditsc.c

kernel-doc: fix new warnings in auditsc.c

Fix new kernel-doc warnings in auditsc.c:

Warning(kernel/auditsc.c:1875): No description found for parameter 'success'
Warning(kernel/auditsc.c:1875): No description found for parameter 'return_code'
Warning(kernel/auditsc.c:1875): Excess function parameter 'pt_regs' description in '__audit_syscall_exit'

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Eric Paris <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>