Create DhcpOption object and make it a SystemApi

This allows OEM apps to pass their custom DHCP options for establishing
network connection.

Bug: 177278970

Test: atest FrameworksNetTests
Test: atest NetworkStackTests

Signed-off-by: Mingguang Xu <mingguangxu@google.com>
Change-Id: I2b8c38ee9a948ad6edb666312c989d27a8ff904b
4 files changed