wpa_supplicant(hidl): Add network param getters

Add getters for all the enterprise network params. These are useful only
for reading out network configs from wpa_supplicant.con for migrating
config store data from N to O. Otherwise, wpa_supplicant should only be
a sink and should only need setter methods.

While there,
Fixed a bug with the eap phase2 method string construction in the HIDL
interface.

Bug: 33583001
Bug: 31497348
Test: Will add gtests for these soon.
Change-Id: I1fe802638b1db96870d0eaf76252b2a35b307523
2 files changed