disp: msm: refactor debugbus to use same helpers

Refactor the debugbus read/logging for sde/dsi/vbif/lutdma to use the
same helpers. Use function pointers to read/write specific hw block
operations. Remove the DBGBUS_FLAGS_DSPP and related checks  as it is
not used. Increase the debugbus block/test-point ranges for all the
blocks to log all the test-points used by hardware.

Change-Id: I07b23d21f9c556eb7575b892f87ab94adfe41116
Signed-off-by: Veera Sundaram Sankaran <[email protected]>