allow all LOG_* levels (#691)

While libvfio-user doesn't use them all, at least SPDK was expecting to
be able to set LOG_NOTICE level, and silently failing. There's no reason
we can't support any valid syslog level.

Signed-off-by: John Levon <[email protected]>
Reviewed-by: Swapnil Ingle <[email protected]>

Author: jlevon

lib/libvfio-user.c

@@ -1755,8 +1755,7 @@ vfu_get_poll_fd(vfu_ctx_t *vfu_ctx)
 EXPORT int
 vfu_setup_log(vfu_ctx_t *vfu_ctx, vfu_log_fn_t *log, int log_level)
 {
-
-    if (log_level != LOG_ERR && log_level != LOG_INFO && log_level != LOG_DEBUG) {
+    if (log_level < LOG_EMERG || log_level > LOG_DEBUG) {
         return ERROR_INT(EINVAL);
     }