[RFC v0 0/1] Add support for CRC64 generation in linker

[binutils@emagii.com]

Here is the first draft of introducing CRC64 generation in the linker

So far it
* reserves room for the CRC (8 bytes)
* Declares a symbol ___CRC64___ for the address of the CRC.
* Allows specifying the polynom (ECMA, ISO or your own)
* Allows for inversion in the CRC calculation (CRC64-WE)
* Allows specifying the area that should be checked.
* Declares the symbol "___CRC64_START__" for the beginning
* Declares the symbol "___CRC64_END__"   for the end (not included)
* Creates a 2kB table which speeds up the CRC calculation
* Can insert the 2kB table into the .text section

It does not yet calculate the CRC of the specified area.
I need to figure out how to access the section(s) covered
for calculating the CRC (between ___CRC64_START___ and ___CRC64_END___)
and then insert the calculated CRC at ___CRC64___ before
the output is generated.

[PATCH v0 1/1] [RFC] Add support for CRC64 generation in linker