Check if the dynamic section is relocated against the ELF files

[pablogsal]

Our trick to see if the dynamic section is relocated may fail in some extreme cases if the library is loaded at a very low memory address and the offset to the dynamic section is very very big.

To avoid the heuristic of checking against the base of the dynamic section to decide addresses are an offset or virtual addresses, we can check against the same value in the original ELF file (which is always an offset) and decide then if it was or not relocated.