[BRIGFE] Improved support for function and module scope group

[BRIGFE] Improved support for function and module scope group
segment variables.

PRM specs defines function and module scope group segment variables
as an experimental feature. However, PRM test suite uses and
hcc relies on them. In addition, hcc assumes certain group variable
layout in its dynamic group segment allocation code.

We cannot have global group memory offsets if we want to
both have kernel-specific group segment size and multiple kernels
calling the same functions that use function scope group memory
variables.

Now group segment is handled by separate book keeping of module
scope and function (kernel) offsets. Each function has a "frame"
in the group segment offset to which is given as an argument.

From-SVN: r253233