libgo: pass flags to recursive make

    
    "make check" runs make recursively to check each package. Pass
    the flags through. So it is possible to run "make check" with
    different settings easily.
    
    Reviewed-on: https://go-review.googlesource.com/76029

From-SVN: r254475

gcc/go/gofrontend/MERGE

-64d570c590a76921cbdca4efb22e4675e19cc809
+b9885a251ae2c43252926dbe1960df5640aa469b
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

libgo/Makefile.am

@@ -1474,7 +1474,7 @@ check-am:
 	@for f in $(TEST_PACKAGES); do \
 	   rm -f $$f-testsum $$f-testlog; \
 	 done
-	-@$(MAKE) -k $(TEST_PACKAGES)
+	-@$(MAKE) $(AM_MAKEFLAGS) -k $(TEST_PACKAGES)
 	@for f in $(TEST_PACKAGES); do \
 	  if test -f $$f-testsum; then \
 	    cat $$f-testsum >> libgo.sum; \
@@ -1488,7 +1488,7 @@ check-multi:
 	$(MULTIDO) $(AM_MAKEFLAGS) DO=check-am multi-do # $(MAKE)
 
 bench:
-	-@$(MAKE) -k $(TEST_PACKAGES) GOBENCH=.
+	-@$(MAKE) $(AM_MAKEFLAGS) -k $(TEST_PACKAGES) GOBENCH=.
 
 MOSTLYCLEANFILES = \
 	s-runtime_sysinfo s-sigtab s-runtime-inc s-zstdpkglist \

libgo/Makefile.in

@@ -3446,7 +3446,7 @@ check-am:
 	@for f in $(TEST_PACKAGES); do \
 	   rm -f $$f-testsum $$f-testlog; \
 	 done
-	-@$(MAKE) -k $(TEST_PACKAGES)
+	-@$(MAKE) $(AM_MAKEFLAGS) -k $(TEST_PACKAGES)
 	@for f in $(TEST_PACKAGES); do \
 	  if test -f $$f-testsum; then \
 	    cat $$f-testsum >> libgo.sum; \
@@ -3460,7 +3460,7 @@ check-multi:
 	$(MULTIDO) $(AM_MAKEFLAGS) DO=check-am multi-do # $(MAKE)
 
 bench:
-	-@$(MAKE) -k $(TEST_PACKAGES) GOBENCH=.
+	-@$(MAKE) $(AM_MAKEFLAGS) -k $(TEST_PACKAGES) GOBENCH=.
 
 mostlyclean-local:
 	find . -name '*.lo' -print | xargs $(LIBTOOL) --mode=clean rm -f