ARM: dts: hammerhead: Change i2c clock rate to 19.2 MHz

* Referenced CAF:
  https://www.codeaurora.org/cgit/quic/la/kernel/msm/commit/arch/arm/boot/dts/msm8974.dtsi?h=kk_3.5&id=2762366bdeb1d2d3bb43ffb21ad3a0908d51551e

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Signed-off-by: LaboDJ <jacopolabardi@gmail.com>

(cherry picked from commit 473dde10200468097b9578c1a527054945340e1a)