hw/mips: Explicit the semi-hosting feature is always required

Disabling the semi-hosting feature leads to build failure:

    LINK    mips-softmmu/qemu-system-mips
  /usr/bin/ld: target/mips/mips-semi.o: in function `helper_do_semihosting':
  target/mips/mips-semi.c:335: undefined reference to `qemu_semihosting_log_out'
  /usr/bin/ld: target/mips/mips-semi.c:338: undefined reference to `qemu_semihosting_log_out'
  collect2: error: ld returned 1 exit status

Add a comment to avoid this feature to be disabled.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Message-Id: <20190701112612.14758-2-philmd@redhat.com>
1 file changed