configure: disable ROMBIOS if qemu-trad is disabled

ROMBIOS only works with qemu-traditional, so if it is disabled,
disable ROMBIOS also.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ ijc -- ran autogen.sh ]

tools/config.h.in

@@ -24,6 +24,9 @@
 /* Qemu traditional enabled */
 #undef HAVE_QEMU_TRADITIONAL
 
+/* ROMBIOS enabled */
+#undef HAVE_ROMBIOS
+
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H