As load_device_tree() returns allocated memory,
we need to free it.
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Fixes: bda19d7bb56 ("hw/rx: Add RX GDB simulator")
Reported-by: Coverity (CID 1432307: RESOURCE_LEAK)
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201102104542.2064745-1-f4bug@amsat.org>