isa_superio_realize() calls isa_fdc_init_drives(), which is defined
in hw/block/fdc.c, so ISA_SUPERIO needs to select the FDC symbol.

Reported-by: John Snow <jsnow@redhat.com>
Fixes: c0ff3795143 ("Introduce a CONFIG_ISA_SUPERIO switch for isa-superio.c")
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 hw/isa/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/isa/Kconfig b/hw/isa/Kconfig
index 55e0003ce40..7216f66a54a 100644
--- a/hw/isa/Kconfig
+++ b/hw/isa/Kconfig
@@ -17,6 +17,7 @@ config ISA_SUPERIO
     bool
     select ISA_BUS
     select PCKBD
+    select FDC
 
 config PC87312
     bool
-- 
2.26.3