wifi: Change WIFI_FEATURE_XXX type from int to long

This change is to avoid issues in assigning signed integer
feature (WIFI_FEATURE_DPP) to long featureSet. The
assignement was resulting in large, signed integer.

Bug: 143363031
Test: atest com.android.wifi.server
Test: Wifi ON/OFF, Connect and data transfer
Test: Added logs and verified feature set saved in iface.
Change-Id: Ic3828e675e49a8c1628368a7e6cf7f01e420bd96
(cherry picked from commit 26ac48bc)