samples: fix the prompt about SAMPLE_VFIO_MDEV_MBOCHS

Change the prompt about SAMPLE_VFIO_MDEV_MBOCHS as
'Build VFIO mbochs example mediated device sample code'.
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Link: https://lore.kernel.org/r/202301301013518438986@zte.com.cnSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

samples/Kconfig

@@ -210,7 +210,7 @@ config SAMPLE_VFIO_MDEV_MDPY_FB
 	  Guest fbdev driver for the virtual display sample driver.
 
 config SAMPLE_VFIO_MDEV_MBOCHS
-	tristate "Build VFIO mdpy example mediated device sample code"
+	tristate "Build VFIO mbochs example mediated device sample code"
 	depends on VFIO
 	select VFIO_MDEV
 	select DMA_SHARED_BUFFER