bsd-user: Remove reference to CONFIG_UNAME_RELEASE

Commit e586822a5 broke the bsd-user build when it removed the
CONFIG_UNAME_RELEASE define but forgot to remove the use of it
in bsd-user. Fix this in the simplest possible way (bsd-user
doesn't make any use at all of the qemu_uname_release variable
except to allow it to be pointlessly set by the user, so this
is all we need to do.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1399648001-20980-1-git-send-email-peter.maydell@linaro.org

bsd-user/main.c

diff --git a/bsd-user/main.c b/bsd-user/main.c
index f81ba55..0f9169d 100644
--- a/bsd-user/main.c
+++ b/bsd-user/main.c
@@ -43,7 +43,7 @@
 #endif
 
 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
-const char *qemu_uname_release = CONFIG_UNAME_RELEASE;
+const char *qemu_uname_release;
 extern char **environ;
 enum BSDType bsd_type;