src/pkg/Makefile: trim per-directory make output except on failure

Not committed to this but it sure makes
the output easier to skim.  With this CL:

$ make
install runtime
install sync/atomic
install sync
install unicode
install utf16
install syscall
install os
...
install ../cmd/govet
install ../cmd/goyacc
install ../cmd/hgpatch
$ make test
test archive/tar
test archive/zip
test asn1
test big
test bufio
...
test path
test path/filepath
TEST FAIL reflect
gotest
rm -f _test/reflect.a
6g -o _gotest_.6 deepequal.go type.go value.go
rm -f _test/reflect.a
gopack grc _test/reflect.a _gotest_.6
all_test.go:210: invalid type assertion: reflect.NewValue(tt.i).(*StructValue) (non-interface type reflect.Value on left)
all_test.go:217: cannot type switch on non-interface value v (type reflect.Value)
all_test.go:218: undefined: IntValue
all_test.go:221: cannot use 132 (type int) as type reflect.Value in function argument
all_test.go:223: cannot use 8 (type int) as type reflect.Value in function argument
all_test.go:225: cannot use 16 (type int) as type reflect.Value in function argument
all_test.go:227: cannot use 32 (type int) as type reflect.Value in function argument
all_test.go:229: cannot use 64 (type int) as type reflect.Value in function argument
all_test.go:231: undefined: UintValue
all_test.go:234: cannot use 132 (type int) as type reflect.Value in function argument
all_test.go:234: too many errors
gotest: "/Users/rsc/g/go/bin/6g -I _test -o _xtest_.6 all_test.go tostring_test.go" failed: exit status 1
make[1]: *** [test] Error 2
make: *** [reflect.test] Error 1

R=r, r2
CC=golang-dev
https://golang.org/cl/4343046
2 files changed