linux/bblayers.conf.sample: Add meta-qt5 layer

Add meta-qt5, new dependency layer of meta-av96.

Signed-off-by: Zbigniew Bodek <zbigniew.bodek@huawei.com>

flavours/linux/bblayers.conf.sample

@@ -19,5 +19,6 @@ BBLAYERS ?= " \
   ##OEROOT##/../meta-openembedded/meta-python \
   ##OEROOT##/../meta-st-stm32mp \
   ##OEROOT##/../meta-st-stm32mp-addons \
+  ##OEROOT##/../meta-qt5 \
   ##OEROOT##/../meta-av96 \
   "