Makefile: Update all Makefiles

This patch updates Makefiles from all examples and add the
configure.ac.
Now it's possible to configure and make all projects for
a specific target (mx5 or mx6) using:

./configure --host=arm-none-linux-gnueabi --verbose --target=<target>
 --prefix=<prefix>

Where:
<target>: mx5 or mx6
<prefix>: local where your i.MX rootfs is

Signed-off-by: Rogerio Pimentel <rogerio.pimentel@freescale.com>