[PATCH liburing v1 2/8] Makefile: Add a '+' char to silence a Makefile warning

[Ammar Faizi <ammarfaizi2@gnuweeb.org>]

When building with `make -jN` where `N` is greater than 1, it shows:

  make[1]: warning: jobserver unavailable: using -j1.  Add '+' to parent make rule.
  make[1]: warning: jobserver unavailable: using -j1.  Add '+' to parent make rule.

This happens because since commit 0d55ea19ccf2 ("version: generate
io_uring_version.h from Makefile.common"), the configure file executes
make command.

Add a '+' char in front of the configure command to silence this
warning.

Cc: Christian Hergert <chergert@redhat.com>
Fixes: 0d55ea19ccf2f34c5dd74f80846f9e5f133746ff ("version: generate io_uring_version.h from Makefile.common")
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 686be4f..4bd7e24 100644
--- a/Makefile
+++ b/Makefile
@@ -18,21 +18,21 @@ partcheck: all
 	@echo "make partcheck => TODO add tests with out kernel support"
 
 runtests: all
 	@$(MAKE) -C test runtests
 runtests-loop: all
 	@$(MAKE) -C test runtests-loop
 runtests-parallel: all
 	@$(MAKE) -C test runtests-parallel
 
 config-host.mak: configure
-	@if [ ! -e "$@" ]; then					\
+	+@if [ ! -e "$@" ]; then				\
 	  echo "Running configure ...";				\
 	  ./configure;						\
 	else							\
 	  echo "$@ is out-of-date, running configure";		\
 	  sed -n "/.*Configured with/s/[^:]*: //p" "$@" | sh;	\
 	fi
 
 ifneq ($(MAKECMDGOALS),clean)
 include config-host.mak
 endif
-- 
Ammar Faizi