hw/core: Add a config switch for the generic loader device

The generic loader device is completely optional. Let's add a proper
config switch for it so that people can disable it if they don't need
it and want to create a minimalistic QEMU binary.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190817101931.28386-9-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

hw/core/Kconfig

@@ -7,6 +7,10 @@ config PTIMER
 config FITLOADER
     bool
 
+config GENERIC_LOADER
+    bool
+    default y
+
 config OR_IRQ
     bool
 

hw/core/Makefile.objs

@@ -21,7 +21,7 @@ common-obj-$(CONFIG_REGISTER) += register.o
 common-obj-$(CONFIG_OR_IRQ) += or-irq.o
 common-obj-$(CONFIG_SPLIT_IRQ) += split-irq.o
 common-obj-$(CONFIG_PLATFORM_BUS) += platform-bus.o
-common-obj-$(CONFIG_SOFTMMU) += generic-loader.o
+common-obj-$(CONFIG_GENERIC_LOADER) += generic-loader.o
 common-obj-$(CONFIG_SOFTMMU) += null-machine.o
 
 obj-$(CONFIG_SOFTMMU) += machine-qmp-cmds.o