R_X86_64_GOT32 and R_X86_64_PLT32 are 32-bit entries but the ELF
RelocationHandler would rewrite longs (64-bit), overwriting the
following bytes with the 64-bit sign-extension thus overwriting
the next instructions.
Rewrite int (32-bit) instead and properly relocate entries using
addend and offset fields as defined in AMD64 ABI.
Signed-off-by: Andy Roulin <andy.roulin@gmail.com>