wavpackdec: Add floating point format support

This commit negotiate F32 audio format if MODE_FLOAT used in wavpack file.
Wavpack float mode is always in 32-bit IEEE format.

The following pipeline plays distorted audio if source file is encoded in float mode:
gst-launch-1.0 filesrc ... ! wavpackparse ! wavpackdec ! pulsesink

Part-of: <gstreamer/gst-plugins-good!896>
35 jobs for !896 with backport-mr-894-into-1.18-fix-wavpack-f32 in 58 minutes and 9 seconds (queued for 5 seconds)
detached
Status Job ID Name Coverage
  Build Docker
passed #7827404
alpine amd64 manifest builder docker

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android docker

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cerbero fedora amd64 docker

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fedora amd64 docker

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gst-indent amd64 docker

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  Preparation
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gst indent

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manifest

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  Build
passed #7827416
gstreamer
build cerbero cross-android universal

00:08:39

passed #7828320
gst-ios-14.3
build cerbero cross-ios universal

00:19:50

passed #7827417
gstreamer
build cerbero cross win32

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gstreamer
build cerbero cross win64

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gstreamer
build cerbero fedora x86_64

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gst-macos-11.1
build cerbero macos x86_64

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build clang fedora x86_64

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manual #7827414
docker windows 1809 allowed to fail manual
build msys2
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build nodebug fedora x86_64

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build static fedora x86_64

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build static nodebug fedora x86_64

00:04:16

passed #7827412
docker windows 1809
build vs2017 amd64

00:09:27

passed #7827413
docker windows 1809
build vs2017 x86

00:09:11

failed #7827420
gst-ios-14.3
build cerbero cross-ios universal

00:18:55

failed #7827886
gst-ios-14.3
build cerbero cross-ios universal

00:17:56

failed #7827410
build static nodebug fedora x86_64

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  Test
passed #7827421
gstreamer
check fedora

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passed #7827422
gstreamer
integration testsuites fedora 1/4

00:13:23

passed #7827423
gstreamer
integration testsuites fedora 2/4

00:15:45

passed #7827424
gstreamer
integration testsuites fedora 3/4

00:11:51

passed #7827425
gstreamer
integration testsuites fedora 4/4

00:26:58

passed #7827427
gstreamer
valgrind bad

00:05:20

passed #7836606
gstreamer
valgrind ges

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passed #7827426
gstreamer
valgrind good

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failed #7827428
gstreamer
valgrind ges

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  Integrate
passed #7827429
cross-android universal examples

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passed #7827431
gst-ios-14.3
cross-ios universal examples

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passed #7827430
documentation

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