staging: unisys: visorbus: Remove unneeded checks for valid variable addr

The 'retry' variable created in handle_command() is statically allocated,
and its address is never set to NULL. Therefore conditionals to verify
the validity of the retry variable's address are unnecessary.

Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David Binder <david.binder@unisys.com>
Signed-off-by: David Kershner <david.kershner@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>