arm64: dts: qcom: sm6115: use correct size for VBIF regions

arm64: dts: qcom: sm6115: use correct size for VBIF regions

Use allocated region size for VBIF regions as defined by the docs
(0x3000) instead of just using the last register address.

Suggested-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250415-drm-msm-dts-fixes-v1-12-90cd91bdd138@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>