The default Jlink GDB command (monitor reset halt) is invalid if it is written in one line. It needs to be written in two lines.

Write it like this

monitor halt
monitor reset

 

qt-creator-13.0.2\src\plugins\baremetal\debugservers\gdb

QString JLinkGdbServerProvider::defaultInitCommands()
{
    return

{"set remote hardware-breakpoint-limit 6\n"             "set remote hardware-watchpoint-limit 4\n"             "monitor halt\n"             "monitor reset\n"             "load\n"             "monitor halt \n"             "monitor reset\n"}

;
}

QString JLinkGdbServerProvider::defaultResetCommands()
{
    return

{"monitor halt\n"             "monitor reset\n"}

;
}