ARM: dts: qcom: ipq4019: fix high resolution timer

Cherry-picked from CAF QSDK repo.
Original commit message:
The kernel is failing in switching the timer for high resolution
mode and clock source operates in 10ms resolution. The always-on
property needs to be given for timer device tree node to make
clock source working in 1ns resolution.

Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Pavel Kubelun <be.dissent@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Tested-by: Robert Marko <robert.marko@sartura.hr>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Link: https://lore.kernel.org/r/20200403114040.349787-1-robert.marko@sartura.hr


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