APM: remove unnecessary check

STREAM_DEFAULT is actually a negative value. When casting to uint it
will result in a very large number which will fail the test for having a
consistent stream value before sending to APM.

Remove this check since the conversion code before checks for stream
validity.

Flag: EXEMPT bugfix
Test: manual
Bug: 361461410
Bug: 361576207
Change-Id: Ib023bdbcba48311a906128bd7394106a01e47dee