wifi: Remove active instance check in Aidl implementation

SoftApManager has handled instance failure and do check to cover
the use case which failure happen before info is updated.
No need to handle in aidl and make sure the framework handle
failure before instance infor is ready.

Flag: EXEMPT bugfix
Bug: 412558191
Test: atest -c HostapdHalAidlImpTest
Change-Id: Iea6357f0936ee9dc4d93a5942c67a325f5ed9b1d
2 files changed