configure: remove --oss-lib

OSS is a kernel API, so the option should not be needed.  The library
is used on NetBSD, where OSS is emulated, so keep the variable.

Cc: Gerd Hoffman <kraxel@redhat.com>
Cc: Volker Rümelin <vr_qemu@t-online.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20211007130630.632028-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

configure

@@ -1007,8 +1007,6 @@ for opt do
   ;;
   --enable-gettext) gettext="enabled"
   ;;
-  --oss-lib=*) oss_lib="$optarg"
-  ;;
   --audio-drv-list=*) audio_drv_list="$optarg"
   ;;
   --block-drv-rw-whitelist=*|--block-drv-whitelist=*) block_drv_rw_whitelist=$(echo "$optarg" | sed -e 's/,/ /g')
@@ -1817,7 +1815,6 @@ Advanced options (experts only):
   --disable-slirp          disable SLIRP userspace network connectivity
   --enable-tcg-interpreter enable TCI (TCG with bytecode interpreter, experimental and slow)
   --enable-malloc-trim     enable libc malloc_trim() for memory optimization
-  --oss-lib                path to OSS library
   --cpu=CPU                Build for host CPU [$cpu]
   --with-coroutine=BACKEND coroutine backend. Supported options:
                            ucontext, sigaltstack, windows