* configure: s/egrep/grep -E/

`egrep` is deprecated.

configure

@@ -18,7 +18,7 @@ rm -f config.mk builds/unix/unix-def.mk builds/unix/unix-cc.mk
 # respect GNUMAKE environment variable for backward compatibility
 if test "x$GNUMAKE" = x; then
   if test "x$MAKE" = x; then
-    if test "x`make -v 2>/dev/null | egrep 'GNU|makepp'`" = x; then
+    if test "x`make -v 2>/dev/null | grep -E 'GNU|makepp'`" = x; then
       MAKE=gmake
     else
       MAKE=make
@@ -28,7 +28,7 @@ else
   MAKE=$GNUMAKE
 fi
 
-if test "x`$MAKE -v 2>/dev/null | egrep 'GNU|makepp'`" = x; then
+if test "x`$MAKE -v 2>/dev/null | grep -E 'GNU|makepp'`" = x; then
   echo "GNU make (>= 3.81) or makepp (>= 2.0) is required to build FreeType2." >&2
   echo "Please try" >&2
   echo >&2