Fix broken autoconf test for random number source.

Hopefully this fixes buildfarm member jacana.

Discussion: https://www.postgresql.org/message-id/be25aa16-2f06-b7d1-8810-c69489a0e70b@dunslane.net

configure

@@ -15022,7 +15022,7 @@ fi
 if test "$enable_strong_random" = "yes" && test x"$USE_OPENSSL_RANDOM" = x"" && test x"$USE_WIN32_RANDOM" = x"" && test x"$USE_DEV_URANDOM" = x"" ; then
   if test x"$with_openssl" = x"yes" ; then
     USE_OPENSSL_RANDOM=1
-  elif test "$PORTNAME" = x"win32" ; then
+  elif test "$PORTNAME" = "win32" ; then
     USE_WIN32_RANDOM=1
   else
     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for /dev/urandom" >&5

configure.in

@@ -1981,7 +1981,7 @@ fi
 if test "$enable_strong_random" = "yes" && test x"$USE_OPENSSL_RANDOM" = x"" && test x"$USE_WIN32_RANDOM" = x"" && test x"$USE_DEV_URANDOM" = x"" ; then
   if test x"$with_openssl" = x"yes" ; then
     USE_OPENSSL_RANDOM=1
-  elif test "$PORTNAME" = x"win32" ; then
+  elif test "$PORTNAME" = "win32" ; then
     USE_WIN32_RANDOM=1
   else
     AC_CHECK_FILE([/dev/urandom], [], [])