Merge core only libs into the target make-files.
Use base-hw specific Board drivers that inherit
from generic Board_base.
Use Page_flags::access_t instead of additional
page_flags_t.
Fix#570
There is no obvious reason for having two different SPEC variables, definitions,
and pathes for the Pandaboard platform. It even lead to problems regarding the
omap4 framebuffer driver (look at issue #505 and #506).
