gdbstub/user: rename and use bool for running_state

This is just a clean-up to document what we using the running variable
for in user-mode.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20260203115201.2387721-12-alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
1 file changed