diag: Make fixes to diag_switch_logging

Diag driver holds on to the socket process task structure even
after signaling the process to exit. This patch clears the internal
handle after signaling.

Signed-off-by: Ravi Aravamudhan <aravamud@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>

drivers/char/diag/diagchar_core.c

@@ -906,6 +906,7 @@ int diag_switch_logging(unsigned long ioarg)
 				pr_err("socket process, status: %d\n",
 					status);
 			}
+			driver->socket_process = NULL;
 		}
 	} else if (driver->logging_mode == SOCKET_MODE) {
 		driver->socket_process = current;