Staging: fbtft: Remove debug messages related to DEBUG_WRITE_VMEM

Remove debug messages related to fbtft_par_dbg(DEBUG_WRITE_VMEM.. )
as this info can be obtained using kernel function tracer

Signed-off-by: Shraddha Barke <shraddha.6596@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>