build: move qapi/ objects to nested Makefile.objs

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Makefile.objs

@@ -375,10 +375,7 @@ libcacard-y = cac.o event.o vcard.o vreader.o vcard_emul_nss.o vcard_emul_type.o
 ######################################################################
 # qapi
 
-qapi-nested-y = qapi-visit-core.o qapi-dealloc-visitor.o qmp-input-visitor.o
-qapi-nested-y += qmp-output-visitor.o qmp-registry.o qmp-dispatch.o
-qapi-nested-y += string-input-visitor.o string-output-visitor.o
-qapi-obj-y = $(addprefix qapi/, $(qapi-nested-y))
+qapi-obj-y = qapi/
 
 common-obj-y += qmp-marshal.o qapi-visit.o qapi-types.o
 common-obj-y += qmp.o hmp.o
@@ -405,6 +402,7 @@ QEMU_CFLAGS+=$(GLIB_CFLAGS)
 nested-vars += \
 	block-obj-y \
 	qom-obj-y \
+	qapi-obj-y \
 	user-obj-y \
 	common-obj-y \
 	extra-obj-y

qapi/Makefile.objs

+qapi-obj-y = qapi-visit-core.o qapi-dealloc-visitor.o qmp-input-visitor.o
+qapi-obj-y += qmp-output-visitor.o qmp-registry.o qmp-dispatch.o
+qapi-obj-y += string-input-visitor.o string-output-visitor.o