Trivial: Fix Makefile typo

Change-Id: Ia108b0359cb2dc4ba2e773117ee7134274a98056
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>
diff --git a/Makefile b/Makefile
index 1a409f6..a40139c 100644
--- a/Makefile
+++ b/Makefile
@@ -496,7 +496,7 @@
 	make -C extras/rpm srpm
 
 dpdk-install-dev:
-	$(call banner,"This command is deprecated. Please use 'make install-ext-libs'")
+	$(call banner,"This command is deprecated. Please use 'make install-ext-deps'")
 	make -C build/external install-$(PKG)
 
 install-ext-deps: