Revert "dts: msm8974: Add blsp2_bam dma node"

Revert this commit to fix regressions on non-dragonboard MSM8974 boards.
This will be put back in after the correct fixes to the bam driver are
accepted that allow remote processor control of the main control registers.

This reverts commit 62bc8179

.

Signed-off-by: Andy Gross <andy.gross@linaro.org>