Add SFMT_MEXP and DSFMT_MEXP macros to config.h

src/configure

@@ -5072,6 +5072,8 @@ EOF
 	if cc_check $_cflags -I. -DSFMT_MEXP=$MEXP >/dev/null 2>&1
 	then
 		echores $MEXP
+	    SFMT_MEXP="#define SFMT_MEXP $MEXP"
+		DSFMT_MEXP="#define DSFMT_MEXP $MEXP"
 		DEFINES="$DEFINES -DSFMT_MEXP=$MEXP -DDSFMT_MEXP=$MEXP"
 	else
 		die "provided $MEXP is not valid!"
@@ -5452,6 +5454,8 @@ $USE_LZMA
 $TRACE_MEMORY_ALLOCS
 $USE_REFERENCE_COUNTING
 $USE_SWIG_DIRECTORS
+$SFMT_MEXP
+$DSFMT_MEXP
 #define OCTAVE_APIVERSION $OCTAVE_APIVERSION
 #define $OS 1
 #define CONFIGURE_OPTIONS "$CONFIGURE_OPTIONS"