Don't link framework aconfig libs for platform targets

The framework links in a select set of aconfig flag libs. Targets that
use `platform_apis: true` can and should reuse these flags, rather than
linking in a redundant copy that conflicts with the bootclasspath.

Bug: 222468116
Test: m + presubmit
Flag: EXEMPT refactor
Change-Id: I90ddd82e886d0ad2a8f1101f0d94e40d4f697ebb
1 file changed