pipewire: Fix recipe style error

pipewire: Fix recipe style error

The bitbake recipe has style guide at
https://www.openembedded.org/wiki/Styleguide

In do_install
Don't use mkdir to create destination directories,
use install -d instead.

Bug-AGL: SPEC-4401

Signed-off-by: duerpei <duep.fnst@fujitsu.com>
Change-Id: Iaf33b842321e0199aee7227077520a12a9a53d74
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/27562
Tested-by: Jenkins Job builder account
ci-image-build: Jenkins Job builder account
ci-image-boot-test: Jenkins Job builder account
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>