i40e: add counters for UDP/IPv4 and IPv4 filters

In preparation for adding code to properly check the mask values, we
will need to know the number of active filters for each type. Add
counters for each filter type. Rename the already existing fd_tcp_rule
to fd_tcp4_filter_cnt to match the style of other names. To avoid style
warnings, avoid assigning multiple parameters at once, and fix up one
other case where we did so previously.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>