OS-4098 move open, close and fcntl into the kernel

*** 72,87 ****
          uint32_t auditing = AU_AUDITING();
          char startchar;
  
          if (filemode & (FSEARCH|FEXEC)) {
                  /*
!                  * Must be one or the other and neither FREAD nor FWRITE
                   * Must not be any of FAPPEND FCREAT FTRUNC FXATTR FXATTRDIROPEN
!                  * XXX: Should these just be silently ignored?
                   */
!                 if ((filemode & (FREAD|FWRITE)) ||
!                     (filemode & (FSEARCH|FEXEC)) == (FSEARCH|FEXEC) ||
                      (filemode & (FAPPEND|FCREAT|FTRUNC|FXATTR|FXATTRDIROPEN)))
                          return (set_errno(EINVAL));
          }
  
          if (startfd == AT_FDCWD) {
--- 72,87 ----
          uint32_t auditing = AU_AUDITING();
          char startchar;
  
          if (filemode & (FSEARCH|FEXEC)) {
                  /*
!                  * Must be one or the other.
                   * Must not be any of FAPPEND FCREAT FTRUNC FXATTR FXATTRDIROPEN
!                  * XXX: Should these just be silently ignored like we
!                  * silently ignore FREAD|FWRITE?
                   */
!                 if ((filemode & (FSEARCH|FEXEC)) == (FSEARCH|FEXEC) ||
                      (filemode & (FAPPEND|FCREAT|FTRUNC|FXATTR|FXATTRDIROPEN)))
                          return (set_errno(EINVAL));
          }
  
          if (startfd == AT_FDCWD) {