amdfwtool: Add a flag to record the second gen instead of romsig

This is for future feature combo, which gets the soc id from fw.cfg in
a loop instead of the command line, and the romsig is not set until
fw.cfg is processed.

Change-Id: Id50311034b46aa1791dcc10b107de4af6c86b927
Signed-off-by: Zheng Bao <fishbaozi@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/63344
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

util/amdfwtool/amdfwtool.h

@@ -276,6 +276,7 @@ typedef struct _amd_cb_config {
 	bool load_mp2_fw;
 	bool multi_level;
 	bool s0i3;
+	bool second_gen;
 	bool have_mb_spl;
 	bool recovery_ab;
 	bool need_ish;