Makefile: hardcoded toolchain path to gcc 4.7

Change-Id: I613d8810420243f9d4c7e500771a919f1bc68069
Signed-off-by: zwliew <zhaoweiliew@gmail.com>
defconfig: hardcode in toolchain path to gcc 4.7

Change-Id: I5b8297568d5543f906cdedd053c0e07d53e97550
Signed-off-by: zwliew <zhaoweiliew@gmail.com>