Building an application with `--profile mbed-os/tools/profiles/debug.json` does not filter correctly for the `TARGET_RELEASE` and `TARGET_DEBUG` folders. In particular: * In a release build, `TARGET_RELEASE` is correctly included in the list of source folders, and `TARGET_DEBUG` is correctly filtered out. * In a debug build, `TARGET_RELEASE` is incorrectly included in the list of source folders, `TARGET_DEBUG` is incorrectly filtered out. It seems like the `RELEASE` label is applied regardless of the debug/release options. Observed with mbed-cli 0.9.10 and 1.0.0. @0xc0170 @meriac