arm64: dts: qcom: sdm845-oneplus: fix reserved-mem

arm64: dts: qcom: sdm845-oneplus: fix reserved-mem

Fix the upper guard and the "removed_region", this fixes the random
crashes which used to occur in memory intensive loads. I'm not sure WHY
the upper guard being 0x2000 instead of 0x1000 doesn't fix this, but it
HAS to be 0x1000.

Fixes: e60fd5ac1f68 ("arm64: dts: qcom: sdm845-oneplus-common: guard rmtfs-mem")
Signed-off-by: Caleb Connolly <caleb@connolly.tech>
Link: https://lore.kernel.org/r/20210720153125.43389-2-caleb@connolly.tech
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>