android: fix 64-bit targets building errors

android: fix 64-bit targets building errors

Patch to avoid the following building errors:

Import includes file: out/target/product/x86_64/obj/EXECUTABLES/su_intermediates/import_includes
target  C: su <= external/koush/Superuser/Superuser/jni/su/su.c
external/koush/Superuser/Superuser/jni/su/su.c: In function 'socket_send_request':
external/koush/Superuser/Superuser/jni/su/su.c:397:5: error: implicit declaration of function 'htonl' [-Werror=implicit-function-declaration]
     write_token(fd, "version", PROTO_VERSION);
     ^

target  C: su <= external/koush/Superuser/Superuser/jni/su/pts.c
Export includes file: external/koush/Superuser/Android.mk -- out/target/product/x86_64/obj/EXECUTABLES/su_intermediates/export_includes
target Prebuilt: clatd.conf (out/target/product/x86_64/obj/ETC/clatd.conf_intermediates/clatd.conf)
external/koush/Superuser/Superuser/jni/su/pts.c: In function 'pts_open':
external/koush/Superuser/Superuser/jni/su/pts.c:121:5: error: implicit declaration of function 'strncpy' [-Werror=implicit-function-declaration]
     strncpy(slave_name, sn_tmp, slave_name_size);
     ^