Fix TAP checks when current directory name contains spaces

Add some quotes in the makefile snippet that creates the temporary
installation, so that it can handle spaces in the directory name and
possibly some other oddities.

src/Makefile.global.in

@@ -316,7 +316,7 @@ endef
 
 define prove_check
 $(MKDIR_P) tmp_check/log
-$(MAKE) -C $(top_builddir) DESTDIR=$(CURDIR)/tmp_check/install install >$(CURDIR)/tmp_check/log/install.log 2>&1
+$(MAKE) -C $(top_builddir) DESTDIR='$(CURDIR)'/tmp_check/install install >'$(CURDIR)'/tmp_check/log/install.log 2>&1
 cd $(srcdir) && TESTDIR='$(CURDIR)' PATH="$(CURDIR)/tmp_check/install$(bindir):$$PATH" $(call add_to_path,$(ld_library_path_var),$(CURDIR)/tmp_check/install$(libdir)) PGPORT='6$(DEF_PGPORT)' $(PROVE) $(PG_PROVE_FLAGS) $(PROVE_FLAGS) t/
 endef