scripts: openocd.sh: Honour V=1

Currently running "make V=1 flash/debug" does not result in the caller
discovering what commands are run to perform the action because make
calls into an opaque script (which then makes complex invokations of
both openocd and gdb). Make the script more transparent by conditionally
enabling enabling tracing within the script.

We also remove the "Done flashing" message. It is pointless because
openocd has already *told* us it has done flashing ["wrote 16384 bytes
from file .../zephyr.elf in 0.802135s (19.947 KiB/s)"]. It is also
potentially misleading since it tells us we are "Done flashing" even
when we failed to flash anything which risks misleading someone
unfamiliar with openocd.

Change-Id: Icaea28c4b00ac10965726dd4502162b7de080953
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

scripts/support/openocd.sh

@@ -43,7 +43,6 @@ do_flash() {
             ${OPENOCD_POST_CMD:+-c $OPENOCD_POST_CMD} \
             -c 'reset run' \
             -c 'shutdown'"
-    echo 'Done flashing'
 }
 
 
@@ -91,6 +90,11 @@ do_debugserver() {
 CMD="$1"
 shift
 
+if [ "$KBUILD_VERBOSE" -eq 1 ]
+then
+	set -x
+fi
+
 case "${CMD}" in
   flash)
     echo "Flashing Target Device"