vme: tsi148: silence uninitialized variable warning

The warning is a false positive.

drivers/vme/bridges/vme_tsi148.c: In function 'tsi148_master_write':
drivers/vme/bridges/vme_tsi148.c:1358:31: warning: 'handler' may be used uninitialized in this function [-Wmaybe-uninitialized]
   vme_unregister_error_handler(handler);
                               ^
drivers/vme/bridges/vme_tsi148.c: In function 'tsi148_master_read':
drivers/vme/bridges/vme_tsi148.c:1260:31: warning: 'handler' may be used uninitialized in this function [-Wmaybe-uninitialized]
   vme_unregister_error_handler(handler);
                               ^

Fixes: 0b049662 ("vme: change bus error handling scheme")
Signed-off-by: Dmitry Kalinkin <dmitry.kalinkin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>