This removes lines that set PKG_BUILD_DIR when the set value is no
different from the default value.

Specifically, the line is removed if the assigned value is:

* $(BUILD_DIR)/$(PKG_NAME)-$(BUILD_VARIANT)/$(PKG_NAME)-$(PKG_VERSION)

  The default PKG_BUILD_DIR was updated[1] to incorporate BUILD_VARIANT
  if it is set, so now this is identical to the default value.

* $(BUILD_DIR)/$(PKG_NAME)-$(BUILD_VARIANT)/$(PKG_SOURCE_SUBDIR)

  if PKG_SOURCE_SUBDIR is set to $(PKG_NAME)-$(PKG_VERSION), making it
  the same as the previous case

* $(BUILD_DIR)/$(PKG_NAME)-$(PKG_VERSION)

  This is the same as the default PKG_BUILD_DIR when there is no
  BUILD_VARIANT.

* $(BUILD_DIR)/[name]-$(PKG_VERSION)

  where [name] is a string that is identical to PKG_NAME

[1]: https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=e545fac8d968864a965edb9e50c6f90940b0a6c9

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

fix Makefile chmod (644)
replace MD5SUM with HASH
add PKG_MIRROR_HASH when PKG_SOURCE_PROTO:=git

(PKG_SOURCE_PROTO:=svn tarballs are not reproducible for now)

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

We are not properly passing down TARGET_CFLAGS and TARGET_CPPFLAGS and
this can be noticed with external toolchains with the following build
error:

mipsel-linux-gnu-gcc -Wall -Wextra -pedantic -Waggregate-return
-Wcast-align -Wcast-qual -Wdisabled-optimization -Wpointer-arith
-Wshadow -Wsign-compare -Wundef -Wwrite-strings -Wbad-function-cast
-Wdeclaration-after-statement -Wmissing-prototypes -Wnested-externs
-Wstrict-prototypes  -O2 -std=c99 -I../lua/ -fPIC   -c -o lpvm.o lpvm.c
lpvm.c:10:17: fatal error: lua.h: No such file or directory
 #include "lua.h"
                 ^
compilation terminated.
make[4]: *** [lpvm.o] Error 1

Re-use COPT to pass our TARGET_CFLAGS and TARGET_CPPFLAGS

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

Signed-off-by: Dirk Chang <dirk@kooiot.com>