Initial Android.mk (miniperl)

config.h entries should then be linked to the repo variables

Only able to build miniperl binary for the moment.

The android/ folder contains two subfolders (mini, micro)
for the generated configs... To be continued...

The actual config sets perl lib root to /data/local/perl,
That could be modified later for a /system integration.

Signed-off-by: Tanguy Pruvot <tanguy.pruvot@gmail.com>
update android config, use some build vars

remove absolute paths in variables, use $ANDROID_BUILD_TOP as
reference.

TODO: remove temporary SYSROOT

remove widechar func defines, bionic implementation is incorrect