package/libsoup3: enable vala bindings

vala bindings are needed to build gssdp 1.6 vapi bindings and avoid the
following build failure since commit
0cd1096eb067542070a991120c953811d6e5e4d1:

FAILED: vala/gssdp-1.6.vapi
/home/buildroot/autobuild/instance-2/output-1/host/bin/vapigen --quiet --library=gssdp-1.6 --directory=/home/buildroot/autobuild/instance-2/output-1/build/gssdp-1.6.3/build/vala --pkg=gio-2.0 --pkg=libsoup-3.0 --metadatadir=/home/buildroot/autobuild/instance-2/output-1/build/gssdp-1.6.3/vala /home/buildroot/autobuild/instance-2/output-1/build/gssdp-1.6.3/build/libgssdp/GSSDP-1.6.gir
error: Package `libsoup-3.0' not found in specified Vala API directories or GObject-Introspection GIR directories

Fixes:
 - http://autobuild.buildroot.org/results/e5fbfc95964beac314c9faffc2c12541d0a10a48

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/libsoup3/libsoup3.mk

@@ -28,8 +28,7 @@ LIBSOUP3_CONF_OPTS = \
 	-Dntlm=disabled \
 	-Dsysprof=disabled \
 	-Dtests=false \
-	-Dtls_check=false \
-	-Dvapi=disabled
+	-Dtls_check=false
 
 ifeq ($(BR2_PACKAGE_BROTLI),y)
 LIBSOUP3_CONF_OPTS += -Dbrotli=enabled
@@ -39,10 +38,10 @@ LIBSOUP3_CONF_OPTS += -Dbrotli=disabled
 endif
 
 ifeq ($(BR2_PACKAGE_GOBJECT_INTROSPECTION),y)
-LIBSOUP3_CONF_OPTS += -Dintrospection=enabled
-LIBSOUP3_DEPENDENCIES += gobject-introspection
+LIBSOUP3_CONF_OPTS += -Dintrospection=enabled -Dvapi=enabled
+LIBSOUP3_DEPENDENCIES += host-vala gobject-introspection
 else
-LIBSOUP3_CONF_OPTS += -Dintrospection=disabled
+LIBSOUP3_CONF_OPTS += -Dintrospection=disabled -Dvapi=disabled
 endif
 
 ifeq ($(BR2_PACKAGE_LIBKRB5),y)