mkimage: Add a quiet mode

Some build systems want to be quiet unless there is a problem. At present
mkimage displays quite a bit of information when generating a FIT file. Add
a '-q' flag to silence this.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/tools/imagetool.c b/tools/imagetool.c
index 916ab96..08d191d 100644
--- a/tools/imagetool.c
+++ b/tools/imagetool.c
@@ -51,7 +51,8 @@
 				 * successful
 				 */
 				if ((*curr)->print_header) {
-					(*curr)->print_header(ptr);
+					if (!params->quiet)
+						(*curr)->print_header(ptr);
 				} else {
 					fprintf(stderr,
 						"%s: print_header undefined for %s\n",
diff --git a/tools/imagetool.h b/tools/imagetool.h
index 24f8f4b..a3ed0f4 100644
--- a/tools/imagetool.h
+++ b/tools/imagetool.h
@@ -73,6 +73,7 @@
 	struct content_info *content_head;	/* List of files to include */
 	struct content_info *content_tail;
 	bool external_data;	/* Store data outside the FIT */
+	bool quiet;		/* Don't output text in normal operation */
 };
 
 /*
diff --git a/tools/mkimage.c b/tools/mkimage.c
index 93d1c16..aefe22f 100644
--- a/tools/mkimage.c
+++ b/tools/mkimage.c
@@ -136,7 +136,7 @@
 	int opt;
 
 	while ((opt = getopt(argc, argv,
-			     "a:A:b:cC:d:D:e:Ef:Fk:K:ln:O:rR:sT:vVx")) != -1) {
+			     "a:A:b:cC:d:D:e:Ef:Fk:K:ln:O:rR:qsT:vVx")) != -1) {
 		switch (opt) {
 		case 'a':
 			params.addr = strtoull(optarg, &ptr, 16);
@@ -216,6 +216,9 @@
 			if (params.os < 0)
 				usage("Invalid operating system");
 			break;
+		case 'q':
+			params.quiet = 1;
+			break;
 		case 'r':
 			params.require_keys = 1;
 			break;