boards/hifive1: add and use custom openocd reset command

boards/hifive1/Makefile.include

@@ -13,6 +13,7 @@ PORT_DARWIN ?= $(firstword $(sort $(wildcard /dev/tty.usbmodem*)))
 include $(RIOTMAKE)/tools/serial.inc.mk
 
 # this board uses openocd
+export OPENOCD_CMD_RESET_RUN=_reset
 include $(RIOTMAKE)/tools/openocd.inc.mk
 
 # use our own openocd script to flash since HiFive1 has reset problems.

boards/hifive1/dist/openocd.cfg

@@ -31,7 +31,8 @@ $_TARGETNAME configure -work-area-phys 0x80000000 -work-area-size 10000 -work-ar
 flash bank onboard_spi_flash fespi 0x20000000 0 0 0 $_TARGETNAME
 #init
 #reset -- This type of reset is not implemented yet
-if {[ info exists pulse_srst]} {
+
+proc _reset {} {
   ftdi_set_signal nSRST 0
   ftdi_set_signal nSRST z
   #Wait for the reset stretcher
@@ -39,6 +40,10 @@ if {[ info exists pulse_srst]} {
   #will incur lots of delays for later commands.
   sleep 1500
 }
+
+if {[ info exists pulse_srst]} {
+  _reset
+}
 #halt
 #flash protect 0 64 last off
 #