net/bnxt: update ULP resource counts

net/bnxt: update ULP resource counts

Update ULP resource counts for Stingray device.
- FW needs some resources for normal operation. Account those
in the resource manager.
- Update the SR ULP requested resource counts to reflect
those available after AFM resources are accounted for.
- Add build option to select either 2 or 4 slot EM entries.
The default is 4 slot entries.

Signed-off-by: Peter Spreadborough <peter.spreadborough@broadcom.com>
Signed-off-by: Farah Smith <farah.smith@broadcom.com>
Reviewed-by: Randy Schacher <stuart.schacher@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>