[PATCH v7 19/20] xen/riscv: provide init_vuart()

For debug purpose is enough to have only print messages from guest what is
now implemented in vsbi_legacy_ecall_handler().

For full guesst console support it will better to have something similar to
[1], thereby there is nothing specific should be done, at least, for now
and init_vuart() is provided to make dom0less code buildable.

[1] https://lore.kernel.org/xen-devel/alpine.DEB.2.22.394.2602041533440.3175371@ubuntu-linux-20-04-desktop/

Signed-off-by: Oleksii Kurochko <[email protected]>
Acked-by: Jan Beulich <[email protected]>
---
Changes in v3-v7:
 - Nothing changed. Only rebase.
---
Changes in v2:
 - Add Acked-by: Jan Beulich <[email protected]>.
---
---
 xen/arch/riscv/dom0less-build.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/xen/arch/riscv/dom0less-build.c b/xen/arch/riscv/dom0less-build.c
index a1fa51b996a7..d1a51b92936a 100644
--- a/xen/arch/riscv/dom0less-build.c
+++ b/xen/arch/riscv/dom0less-build.c
@@ -8,6 +8,14 @@
 
 #include <asm/p2m.h>
 
+int __init init_vuart(struct domain *d, struct kernel_info *kinfo,
+                      const struct dt_device_node *node)
+{
+    /* Nothing to do at the moment */
+
+    return 0;
+}
+
 int __init init_intc_phandle(struct kernel_info *kinfo, const char *name,
                              const int node_next, const void *pfdt)
 {
-- 
2.55.0