autoreconf

Synchronize pg_config.h.in with configure.in (someone must have
forgotten to run autoheader or autoreconf), and clean up some spurious
change in configure introduced by the last commit there.

configure

@@ -850,7 +850,6 @@ with_gnu_ld
 enable_largefile
 enable_float4_byval
 enable_float8_byval
-enable_float8_byval
 '
       ac_precious_vars='build_alias
 host_alias
@@ -861,7 +860,6 @@ LDFLAGS
 LIBS
 CPPFLAGS
 CPP
-CPPFLAGS
 LDFLAGS_EX
 LDFLAGS_SL
 DOCBOOKSTYLE'

src/include/pg_config.h.in

@@ -305,6 +305,9 @@
 /* Define if you have a function readline library */
 #undef HAVE_LIBREADLINE
 
+/* Define to 1 if you have the `selinux' library (-lselinux). */
+#undef HAVE_LIBSELINUX
+
 /* Define to 1 if you have the `ssl' library (-lssl). */
 #undef HAVE_LIBSSL