Fix MSVC builds for previous patch's addition of a src/port file.

(And why in the world is this OBJS list not being scraped from the
corresponding Makefile?)

src/tools/msvc/Mkvcbuild.pm

@@ -56,7 +56,7 @@ sub mkvcbuild
       chklocale.c crypt.c fls.c fseeko.c getrusage.c inet_aton.c random.c
       srandom.c getaddrinfo.c gettimeofday.c inet_net_ntop.c kill.c open.c
       erand48.c snprintf.c strlcat.c strlcpy.c dirmod.c exec.c noblock.c path.c
-      pgcheckdir.c pgmkdirp.c pgsleep.c pgstrcasecmp.c qsort.c qsort_arg.c
+      pgcheckdir.c pg_crc.c pgmkdirp.c pgsleep.c pgstrcasecmp.c qsort.c qsort_arg.c
       sprompt.c thread.c getopt.c getopt_long.c dirent.c rint.c win32env.c
       win32error.c win32setlocale.c);