drm/amdgpu/virt: increase mailbox timeout to 5000ms

When multiple VFs try to enter exclusive mode at the same time, the
looping mechansim doesn't help to ensure each can get it because it
only loops active VFs, then the last one has to wait for a long
interval.
Signed-off-by: Pixel Ding <Pixel.Ding@amd.com>
Reviewed-by: Xiangliang.Yu <Xiangliang.Yu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/mxgpu_vi.h

@@ -23,7 +23,7 @@
 #ifndef __MXGPU_VI_H__
 #define __MXGPU_VI_H__
 
-#define VI_MAILBOX_TIMEDOUT	150
+#define VI_MAILBOX_TIMEDOUT	5000
 #define VI_MAILBOX_RESET_TIME	12
 
 /* VI mailbox messages request */