rtc: add -rtc clock=rt

This will let people use backwards-compatible semantics for devices that
will be affected by the following patches.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/vl.c b/vl.c
index 0fccf50a5d..71a4755faf 100644
--- a/vl.c
+++ b/vl.c
@@ -529,6 +529,8 @@ static void configure_rtc(QemuOpts *opts)
     if (value) {
         if (!strcmp(value, "host")) {
             rtc_clock = host_clock;
+        } else if (!strcmp(value, "rt")) {
+            rtc_clock = rt_clock;
         } else if (!strcmp(value, "vm")) {
             rtc_clock = vm_clock;
         } else {