audio policy: fix preferred input device use in getInputForAttr()

Ignore preferred device rules in Engine::getInputDeviceForAttributes()
when called from getInputforAttr(). The preferred device is already
taken into account directly in getInputForAttr() and the outcome of
Engine::getInputDeviceForAttributes() will vary depending on active
clients with preferred devices which can cause the wrong input profile
to be selected.

Bug: 303079083
Test: make
Flag: com.android.media.audioserver.conditionally_ignore_preferred_input_device
Change-Id: If30333aad2625eec79a180ec9c2959b57cd664da