[source] system/mtd: 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/8ecf7443a42d96234bf1241ae3a8315057c8fa9e

commit 8ecf7443a42d96234bf1241ae3a8315057c8fa9e
Author: Alexandru Ardelean <ardeleanalex at gmail.com>
AuthorDate: Thu Oct 6 09:23:28 2016 +0300

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

diff --git a/package/system/mtd/Makefile b/package/system/mtd/Makefile
index ae1922f..01277d9 100644
--- a/package/system/mtd/Makefile
+++ b/package/system/mtd/Makefile
@@ -31,11 +31,6 @@ define Package/mtd/description
  older OpenWrt releases.
 endef
 
-define Build/Prepare
-	mkdir -p $(PKG_BUILD_DIR)
-	$(CP) ./src/* $(PKG_BUILD_DIR)/
-endef
-
 target=$(firstword $(subst -, ,$(BOARD)))
 
 MAKE_FLAGS += TARGET="$(target)"