build: add to VPATH src and build dirs

In order to make out-of-tree builds and distcheck to work, we should
set the VPATH to look for sources also in srcdir and builddir.

diff --git a/src/shaders/post_processing/gen9/Makefile.am b/src/shaders/post_processing/gen9/Makefile.am
index d58cd9a..527a303 100644 (file)
--- a/src/shaders/post_processing/gen9/Makefile.am
+++ b/src/shaders/post_processing/gen9/Makefile.am
@@ -1,5 +1,5 @@
-SRCDIR = $(top_srcdir)/src/shaders/post_processing/gen8
-VPATH = $(SRCDIR)
+G8A_DIR = $(top_srcdir)/src/shaders/post_processing/gen8
+VPATH = $(G8A_DIR) $(srcdir) $(builddir)
 
 INTEL_PP_PRE_G9B =             \
        conv_p010.g9b           \