[1] removed target_halt() from cortex_m_assert_reset()
It broke debug_reason tracking and the previous reason
was shown after reset halt.
Set debug_reason to DBG_REASON_DBGRQ during reset halt
preparation.
Fixes: [1] commit 226085065b ("target/cortex_m: drop useless target_halt() call")
Reported-by: Marc Schink <dev@zapb.de>
Change-Id: I685618ed158abde11f6e00eeeee1dfa8ed90952d
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: https://review.openocd.org/c/openocd/+/8945
Tested-by: jenkins
Reviewed-by: zapb <dev@zapb.de>