dtc: Implement -d option to write out a dependency file

This will allow callers to rebuild .dtb files when any of the /include/d
.dtsi files are modified, not just the top-level .dts file.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 1 insertions, 0 deletions

diff --git a/srcpos.h b/srcpos.h
index bd7966e..ce980ca 100644
--- a/srcpos.h
+++ b/srcpos.h
@@ -30,6 +30,7 @@ struct srcfile_state {
 	struct srcfile_state *prev;
 };
 
+extern FILE *depfile; /* = NULL */
 extern struct srcfile_state *current_srcfile; /* = NULL */
 
 FILE *srcfile_relative_open(const char *fname, char **fullnamep);