uaccess: correct kernel-doc parameter format

uaccess: correct kernel-doc parameter format

Use the correct kernel-doc function parameter format to avoid kernel-doc
warnings:

Warning: include/linux/uaccess.h:814 function parameter 'uptr' not
 described in 'scoped_user_rw_access_size'
Warning: include/linux/uaccess.h:826 function parameter 'uptr' not
 described in 'scoped_user_rw_access'

Link: https://lkml.kernel.org/r/20260302005229.3471955-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>