[ELF] - simplify Target interface, relocPointsToGot() removed.

https://docs.oracle.com/cd/E19683-01/817-3677/chapter6-26/index.html says:
R_386_GOTPC
Resembles R_386_PC32, except that it uses the address of the global offset table in its calculation. The symbol referenced in this relocation normally is _GLOBAL_OFFSET_TABLE_, which also instructs the link-editor to create the global offset table.

Currently _GLOBAL_OFFSET_TABLE_ has value == zero. And we use GOT address to calculate the relocation. This patch does not changes that. It just removes the method which is used only for x86. So it is close to non functional change.

Differential revision: http://reviews.llvm.org/D14993

llvm-svn: 254088