configure: Disable -Wtautological-type-limit-compare

configure: Disable -Wtautological-type-limit-compare

Clang 10 enables this by default with -Wtype-limit.

All of the instances flagged by this Werror so far have been
cases in which we really do want the compiler to optimize away
the test completely.  Disabling the warning will avoid having
to add ifdefs to work around this.

Cc: Eric Blake <eblake@redhat.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1878628
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200617201309.1640952-5-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>