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>

Fixes the following build error:
hiredis.h:101:24: error: lvalue required as left operand of assignment
             buf[(len)] = '\0';

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

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

Signed-off-by: Daniel Golle <daniel@makrotopia.org>