[source] boot/rbcfg: drop Build/Prepare rule in favor of default one

[LEDE Commits]

blogic pushed a commit to source.git, branch master:
https://git.lede-project.org/5b607bd8d84a53d4c2f4ea240bd61ee3915d1f9d

commit 5b607bd8d84a53d4c2f4ea240bd61ee3915d1f9d
Author: Alexandru Ardelean <ardeleanalex at gmail.com>
AuthorDate: Thu Oct 6 09:40:51 2016 +0300

    boot/rbcfg: drop Build/Prepare rule in favor of default one
    
    Signed-off-by: Alexandru Ardelean <ardeleanalex at gmail.com>
---
 package/boot/rbcfg/Makefile | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/package/boot/rbcfg/Makefile b/package/boot/rbcfg/Makefile
index 51fefd5..9f227b8 100644
--- a/package/boot/rbcfg/Makefile
+++ b/package/boot/rbcfg/Makefile
@@ -26,11 +26,6 @@ define Package/rbcfg/description
  MikroTIK RB-4XX devices.
 endef
 
-define Build/Prepare
-	mkdir -p $(PKG_BUILD_DIR)
-	$(CP) ./src/* $(PKG_BUILD_DIR)/
-endef
-
 define Build/Configure
 endef