[X25]: Avoid divides and sparse warnings

   CHECK   net/x25/af_x25.c
net/x25/af_x25.c:117:46: warning: expensive signed divide
   CHECK   net/x25/x25_facilities.c
net/x25/x25_facilities.c:209:30: warning: expensive signed divide
   CHECK   net/x25/x25_in.c
net/x25/x25_in.c:250:26: warning: expensive signed divide
   CHECK   net/x25/x25_proc.c
net/x25/x25_proc.c:48:11: warning: context imbalance in 'x25_seq_route_start' 
- wrong count at exit
net/x25/x25_proc.c:72:13: warning: context imbalance in 'x25_seq_route_stop' - 
unexpected unlock
net/x25/x25_proc.c:112:11: warning: context imbalance in 
'x25_seq_socket_start' - wrong count at exit
net/x25/x25_proc.c:129:13: warning: context imbalance in 'x25_seq_socket_stop' 
- unexpected unlock
net/x25/x25_proc.c:190:11: warning: context imbalance in 
'x25_seq_forward_start' - wrong count at exit
net/x25/x25_proc.c:215:13: warning: context imbalance in 
'x25_seq_forward_stop' - unexpected unlock
   CHECK   net/x25/x25_subr.c
net/x25/x25_subr.c:362:57: warning: expensive signed divide

Signed-off-by: Eric Dumazet <redacted>

  net/x25/af_x25.c         |    4 ++--
  net/x25/x25_facilities.c |    4 +---
  net/x25/x25_in.c         |    2 +-
  net/x25/x25_proc.c       |    6 ++++++
  net/x25/x25_subr.c       |    2 +-
  5 files changed, 11 insertions(+), 7 deletions(-)