osdep: fix HAVE_BROKEN_SIZE_MAX case

osdep: fix HAVE_BROKEN_SIZE_MAX case

While config-host.mak entries are expanded to "1" for compatibility with
create-config.sh, tests done directly in meson.build expand to the empty
string and cannot be placed to the right of the && operator.  Adjust
osdep.h after commit e46bd55d9c ("configure: convert HAVE_BROKEN_SIZE_MAX
to meson", 2021-07-06) changed the way HAVE_BROKEN_SIZE_MAX is defined.

Reported-by: Frederic Bezies <fredbezies@gmail.com>
Fixes: e46bd55d9c ("configure: convert HAVE_BROKEN_SIZE_MAX to meson", 2021-07-06)
Resolves: #463
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>