ARM: dts: qcom: ipq8064: add gsbi6 missing definition

Add gsbi6 missing definition for ipq8064.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Tested-by: Jonathan McDowell <noodles@earth.li>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220707010943.20857-3-ansuelsmth@gmail.com