This bug was spotted by cppcheck.

Using g_try_malloc0 (as does the linux-user code) fixes this.

v2:
Use g_free in bsdload.c, too. Thanks to Peter Maydell for this hint.
Signed-off-by: NStefan Weil <sw@weilnetz.de>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>