Move wifi.proto to shared service .jar

Changes to ART are causing nano-proto's generated java base classes
to conflict with their duplicates in other projects, leading to a
NullPointerException.

Moving wifi.proto to the same build as other framework service protos in order
for them to share and not generate a duplicate CodedOutputByteBufferNano
classes.

wifi.proto previously lived at:
frameworks/opt/net/wifi/service/proto/wifi.proto

Merged-In: Ia30391453e8d6614edc7f4397e9c17cfe95cf63e
Bug: 32261442
Test: Builds, and existing Unit tests pass
Change-Id: Ia30391453e8d6614edc7f4397e9c17cfe95cf63e