futex: add missing function parameter comments

futex: add missing function parameter comments

Correct or add the missing function parameter kernel-doc comments
to avoid warnings:

Warning: include/asm-generic/futex.h:38 function parameter 'op' not
 described in 'futex_atomic_op_inuser_local'
Warning: include/asm-generic/futex.h:38 function parameter 'oparg' not
 described in 'futex_atomic_op_inuser_local'
Warning: include/asm-generic/futex.h:38 function parameter 'oval' not
 described in 'futex_atomic_op_inuser_local'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260304005008.409858-1-rdunlap@infradead.org