arm64: dts: qcom: sc7180: Fix I2C/UART numbers 2, 4, 7, and 9

Commit f4a73f5e ("pinctrl: qcom: sc7180: Add new qup functions")
has landed which means that we absolutely need to use the proper names
for the pinmuxing for I2C/UART numbers 2, 4, 7, and 9.  Let's do it.

For reference:
- If you get only one of this commit and the pinctrl commit then none
  of I2C/UART 2, 4, 7, and 9 will work.
- If you get neither of these commits then I2C 2, 4, 7, and 9 will
  work but not UART.

...but despite the above it should be fine for this commit to land in
the Qualcomm tree because sc7180.dtsi only exists there (it hasn't
made it to mainline).

Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Rajendra Nayak <rnayak@codeaurora.org>
Fixes: ba3fc649 ("arm64: dts: sc7180: Add qupv3_0 and qupv3_1")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191217130352.1.Id8562de45e8441cac34699047e25e7424281e9d4@changeid


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>