lib: Test against available swap

Even if we ignore the double-accounting bug in Linux, we need to be sure
that the remaining swapspace is adequate for running our test as the
system may be under load before we even start.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

lib/intel_drm.c

@@ -132,7 +132,7 @@ intel_get_total_swap_mb(void)
 	ret = sysinfo(&sysinf);
 	assert(ret == 0);
 
-	retval = sysinf.totalswap;
+	retval = sysinf.freeswap;
 	retval *= sysinf.mem_unit;
 #elif defined(HAVE_SWAPCTL) /* Solaris */
 	long pagesize = sysconf(_SC_PAGESIZE);