hid: intel-ish-hid: Fix uninitialized variable 'rv' in ish_fw_xfer_direct_dma

Fix the uninitialized symbol 'rv' in the function ish_fw_xfer_direct_dma
to resolve the following warning from the smatch tool:
drivers/hid/intel-ish-hid/ishtp-fw-loader.c:714 ish_fw_xfer_direct_dma()
error: uninitialized symbol 'rv'.
Initialize 'rv' to 0 to prevent undefined behavior from uninitialized
access.

Cc: stable@vger.kernel.org
Fixes: 91b2281 ("HID: intel-ish-hid: ISH firmware loader client driver")
Signed-off-by: SurajSonawane2415 <surajsonawane0215@gmail.com>
Link: https://patch.msgid.link/20241004075944.44932-1-surajsonawane0215@gmail.com
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>

Author: SurajSonawane2415

drivers/hid/intel-ish-hid/ishtp-fw-loader.c

@@ -635,7 +635,7 @@ static int ish_fw_xfer_direct_dma(struct ishtp_cl_data *client_data,
 				  const struct firmware *fw,
 				  const struct shim_fw_info fw_info)
 {
-	int rv;
+	int rv = 0;
 	void *dma_buf;
 	dma_addr_t dma_buf_phy;
 	u32 fragment_offset, fragment_size, payload_max_size;