Fix isolation tester Makefile so that it runs in a VPATH build

src/test/isolation/Makefile

@@ -68,7 +68,7 @@ maintainer-clean: distclean
 	rm -f specparse.c specscanner.c
 
 installcheck: all
-	./pg_isolation_regress --schedule=$(srcdir)/isolation_schedule
+	./pg_isolation_regress --inputdir=$(srcdir) --schedule=$(srcdir)/isolation_schedule
 
 check: all
-	./pg_isolation_regress --temp-install=./tmp_check --top-builddir=$(top_builddir) --schedule=$(srcdir)/isolation_schedule
+	./pg_isolation_regress --temp-install=./tmp_check --inputdir=$(srcdir) --top-builddir=$(top_builddir) --schedule=$(srcdir)/isolation_schedule

src/test/isolation/README

@@ -26,7 +26,7 @@ Test specification
 ==================
 
 Each isolation test is defined by a specification file, stored in the specs
-subdirectory. A test specification consists of five parts, in this order:
+subdirectory. A test specification consists of four parts, in this order:
 
 setup { <SQL> }