[source] imagebuilder: make submake invocations less verbose

[LEDE Commits]

jow pushed a commit to source.git, branch lede-17.01:
https://git.lede-project.org/1d0f7e3136c7f72852fe91c1ec95863b1f4ace15

commit 1d0f7e3136c7f72852fe91c1ec95863b1f4ace15
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Mon Aug 1 18:26:05 2016 +0200

    imagebuilder: make submake invocations less verbose
    
    Use silent make invocations for sub-makes like build_image or checksum to
    avoid bloating the IB output with non-status info.
    
    Signed-off-by: Jo-Philipp Wich <jo at mein.io>
    (cherry picked from commit 0d1765b4ba2575ad7dbfbea5e5d04ba1224cdc0a)
---
 target/imagebuilder/files/Makefile | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/target/imagebuilder/files/Makefile b/target/imagebuilder/files/Makefile
index af633b2..baa0e1f 100644
--- a/target/imagebuilder/files/Makefile
+++ b/target/imagebuilder/files/Makefile
@@ -123,9 +123,9 @@ _call_image: staging_dir/host/.prereq-build
 ifneq ($(USER_FILES),)
 	$(MAKE) copy_files
 endif
-	$(MAKE) package_postinst
-	$(MAKE) build_image
-	$(MAKE) checksum
+	$(MAKE) -s package_postinst
+	$(MAKE) -s build_image
+	$(MAKE) -s checksum
 
 package_index: FORCE
 	@echo
@@ -194,7 +194,7 @@ ifneq ($(PROFILE),)
   endif
 endif
 	(unset PROFILE FILES PACKAGES MAKEFLAGS; \
-	$(MAKE) _call_image \
+	$(MAKE) -s _call_image \
 		$(if $(PROFILE),USER_PROFILE="$(PROFILE_FILTER)") \
 		$(if $(FILES),USER_FILES="$(FILES)") \
 		$(if $(PACKAGES),USER_PACKAGES="$(PACKAGES)") \