wpa_supplicant(hidl): Mask out unsupported values

Looks like some older devices have some invalid/unsupported entries in
their wpa_supplicant.conf. Mask them out when retrieving the values in
the HIDL interface.

Also,
Fixed few variable names.

Bug: 35915083
Test: Testing the build on the reporter.
Change-Id: Ib743a5234753ae1043fefb9e0a8a58f9786b4031
1 file changed