[shotwell] Fix make distcheck

[Jens Georg <jensgeorg src gnome org>]

commit e59f3184266543c057c96290b95a5392c31d9bbf
Author: Jens Georg <mail jensge org>
Date:   Sun Dec 11 16:15:04 2016 +0100

    Fix make distcheck
    
    Signed-off-by: Jens Georg <mail jensge org>

 shotwell.am |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/shotwell.am b/shotwell.am
index ceb5fd2..bb2c53b 100644
--- a/shotwell.am
+++ b/shotwell.am
@@ -27,11 +27,13 @@ nodist_shotwell_SOURCES = \
        resource.c
 MOSTLYCLEANFILES += resource.c
 
-shotwell_resource_deps = $(shell $(GLIB_COMPILE_RESOURCES) \
-               --generate-dependencies $(abs_top_srcdir)/org.gnome.Shotwell.gresource.xml)
+shotwell_resource_deps := $(shell $(GLIB_COMPILE_RESOURCES) \
+       --sourcedir=$(abs_top_srcdir) \
+       --generate-dependencies $(abs_top_srcdir)/org.gnome.Shotwell.gresource.xml)
 
 resource.c: org.gnome.Shotwell.gresource.xml $(shotwell_resource_deps)
        $(AM_V_GEN)$(GLIB_COMPILE_RESOURCES) --target=$@ \
+               --sourcedir=$(abs_top_srcdir) \
                --generate $<
 
 shotwell_SOURCES = \