media: usb: cx231xx-417: fix a memory leak bug

In cx231xx_load_firmware(), 'p_buffer' is allocated through vmalloc() to
hold the firmware. However, after the usage, it is not deallocated, leading
to a memory leak bug.
Signed-off-by: NWenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: NHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/usb/cx231xx/cx231xx-417.c

@@ -1051,6 +1051,7 @@ static int cx231xx_load_firmware(struct cx231xx *dev)
 	p_current_fw = p_fw;
 	vfree(p_current_fw);
 	p_current_fw = NULL;
+	vfree(p_buffer);
 	uninitGPIO(dev);
 	release_firmware(firmware);
 	dprintk(1, "Firmware upload successful.\n");