Correct the declaration of hipBindTexture2D()

The texture reference needs to be passed as a constant pointer.

Change-Id: Idde461f0f328ac87ce677b6bab3203161b514cbf

vdi/hip_texture.cpp

@@ -457,7 +457,7 @@ hipError_t ihipBindTexture2D(size_t* offset,
 }
 
 hipError_t hipBindTexture2D(size_t* offset,
-                            textureReference* texref,
+                            const textureReference* texref,
                             const void* devPtr,
                             const hipChannelFormatDesc* desc,
                             size_t width,