Define various symbols conditionally in shared libraries executables

[Wilco Dijkstra]

Hi Nick,

> The script itself is the ld/scriptempl/elf.sc file in the linker sources
> although the line in question is actually the invocation of the 
> OTHER_BSS_END_SYMBOLS macro which, for the aarch64, is defined in
> ld/emulparams/aarch64elf.sh.  It appears that the problem is a simple
> typo:
>
>OTHER_BSS_END_SYMBOLS="${CREATE_SHLIB+PROVIDE (}_bss_end__ = .${CREATE_SHLIB+)}; __bss_end__ = .${CREATE_SHLIB+)};"
>
> The definition of the __bss_end__ symbol should be conditional upon CREATE_SHLIB
> being defined.  (As is done for the _bss_end__ symbol).
>
> So I am checking in the obvious patch to fix this.

Thanks for that, that fixes it indeed! 

Wilco