VisionBuf: add idx property

Author: incognitojam

msgq/visionipc/visionipc.pxd

@@ -26,6 +26,7 @@ cdef extern from "msgq/visionipc/visionbuf.h":
     size_t height
     size_t stride
     size_t uv_offset
+    size_t idx
     cl_mem buf_cl
     void set_frame_id(uint64_t id)
 

msgq/visionipc/visionipc_pyx.pyx

@@ -55,6 +55,9 @@ cdef class VisionBuf:
   def uv_offset(self):
     return self.buf.uv_offset
 
+  @property
+  def idx(self):
+    return self.buf.idx
 
 cdef class VisionIpcServer:
   cdef cppVisionIpcServer * server