crypto: improve ipsecmb build time

Type: improvement

This change disables building of ipsecmb test and perf targets to
reduce the build time.
IpsecMB test and perf targets are not neeeded and not used by VPP.

Signed-off-by: PiotrX Kleski <piotrx.kleski@intel.com>
Reviewed-by: Fan Zhang <roy.fan.zhang@intel.com>
Change-Id: I7c3449f7f4ce9a2e70ca21a00fd510691dab87d0
diff --git a/build/external/packages/ipsec-mb.mk b/build/external/packages/ipsec-mb.mk
index bed25c3..270387d 100644
--- a/build/external/packages/ipsec-mb.mk
+++ b/build/external/packages/ipsec-mb.mk
@@ -29,7 +29,7 @@
 endef
 
 define  ipsec-mb_build_cmds
-	@make -C $(ipsec-mb_src_dir) -j \
+	@make -C $(ipsec-mb_src_dir)/lib -j \
 	  SHARED=n \
 	  SAFE_PARAM=n \
 	  SAFE_LOOKUP=n \