softethervpn: add package name to build dir

Current build dir is set at just v$(PKG_VERSION).

Signed-off-by: Eneas U de Queiroz <cote2004-github@yahoo.com>

net/softethervpn/Makefile

@@ -18,8 +18,8 @@ PKG_SOURCE:=softether-src-v$(PKG_VERSION)-$(PKG_VERREL).tar.gz
 PKG_SOURCE_URL:=http://www.softether-download.com/files/softether/v$(PKG_VERSION)-$(PKG_VERREL)-$(PKG_VERDATE)-tree/Source_Code/
 PKG_HASH:=b946dec3da5833ad2be69125224784b8a8e2a4149297d0c0a907ba0e1c4535f8
 
-PKG_BUILD_DIR:=$(BUILD_DIR)/v$(PKG_VERSION)
-HOST_BUILD_DIR:=$(BUILD_DIR_HOST)/v$(PKG_VERSION)
+PKG_BUILD_DIR:=$(BUILD_DIR)/$(PKG_NAME)/v$(PKG_VERSION)
+HOST_BUILD_DIR:=$(BUILD_DIR_HOST)/$(PKG_NAME)/v$(PKG_VERSION)
 
 PKG_LICENSE:=GPL-2.0
 PKG_LICENSE_FILES:=COPYING