4a: bump 4a-softmixer & 4a-hal-generic to latest version

4a: bump 4a-softmixer & 4a-hal-generic to latest version

In order to fix AGL-Bug: SPEC-2387,
bump 4a-hal-generic and 4a-softmixer to the latest version

This respectively brings the following commits (all on the merged
branch are cherry-picked from master):

4a-hal-generic:
*   d47f47e Merge branch 'sandbox/tbultel/spec-2387' into guppy
|\
| * 33fb965 .gitignore: added wildcard for build directory
| * 43efc33 bluealsa plugin: do not do anything when the HAL is not ready
| * db4eeea bluealsa plugin: get the sampling rate from the transport
|/

4a-softmixer:
*   b520613 Merge branch 'sandbox/tbultel/spec-2387' into guppy
|\
| * 43df828 loops/avirt: forget saved loops after creation
| * 622096c plug route: added a calculation for the number of physical c..
| * c950295 streams: improved log output
| * 7520fbf core-pcm: fixed channels setting issues
| * 293fe69 core pcm: use the same model for writing and reading audio
| * e355716 pcm plugs: rework the alsa config cleanup
| * eb45566 alsa-api-pcm: added an 'optional' parameter
| * 93bf6e6 alsa-transaction: simplify the cleanup
| * bb70b48 alsa-api-pcm: added support of quirks
| * 93ca785 alsa-utils-dump: added missing ending null char
|/

Change-Id: I7faa8acf77bc903abccde5b48f30728bfac535aa
Signed-off-by: Thierry Bultel <thierry.bultel@iot.bzh>