support/scripts/mkmakefile: make wrapper silent by default

Suppose we use Makefile wrapper and build some project out of
buildroot tree (O=...). A command like "make
busybox-all-external-deps" will output the string "uname 022 && make
..." to stdout before the usefull information. It pollutes stdout. At
the same time if we use the same command in the buildroot source-tree
then we don't get the additional output. This patch makes wrapper
silent by default. People who prefer to see more verbose output can
use V=1.

Signed-off-by: Serj Kalichev <serj.kalichev@gmail.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

support/scripts/mkmakefile

@@ -20,6 +20,13 @@ echo "  GEN     $2/Makefile"
 cat << EOF > $2/Makefile
 # Automatically generated by $0: don't edit
 
+ifeq ("\$(origin V)", "command line")
+VERBOSE := \$(V)
+endif
+ifneq (\$(VERBOSE),1)
+Q := @
+endif
+
 lastword = \$(word \$(words \$(1)),\$(1))
 makedir := \$(dir \$(call lastword,\$(MAKEFILE_LIST)))
 
@@ -33,7 +40,7 @@ MAKEFLAGS += --no-print-directory
 all	:= \$(filter-out Makefile,\$(MAKECMDGOALS))
 
 _all:
-	umask 0022 && \$(MAKE) \$(MAKEARGS) \$(all)
+	\$(Q)umask 0022 && \$(MAKE) \$(MAKEARGS) \$(all)
 
 Makefile:;