staging: r8188eu: check firmware header existence before access

We should access the fields of fwhdr only if the check for firmware
header existence is true. Move the affected code into the if block
that checks firmware header existence.
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20220417175441.13830-9-straube.linux@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/core/rtw_fw.c

@@ -256,14 +256,13 @@ int rtl8188e_firmware_download(struct adapter *padapter)
 	fw_data = dvobj->firmware.data;
 	fw_size = dvobj->firmware.size;
 
-	/*  To Check Fw header. Added by tynli. 2009.12.04. */
 	fwhdr = (struct rt_firmware_hdr *)dvobj->firmware.data;
 
-	pr_info_once("%sFirmware Version %d, SubVersion %d, Signature 0x%x\n",
-		     DRIVER_PREFIX, le16_to_cpu(fwhdr->version), fwhdr->subversion,
-		     le16_to_cpu(fwhdr->signature));
-
 	if (IS_FW_HEADER_EXIST(fwhdr)) {
+		pr_info_once("%sFirmware Version %d, SubVersion %d, Signature 0x%x\n",
+			     DRIVER_PREFIX, le16_to_cpu(fwhdr->version), fwhdr->subversion,
+			     le16_to_cpu(fwhdr->signature));
+
 		fw_data = fw_data + sizeof(struct rt_firmware_hdr);
 		fw_size = fw_size - sizeof(struct rt_firmware_hdr);
 	}