Change resolveRelocation parameters so the relocations can find placeholder values...

Change resolveRelocation parameters so the relocations can find placeholder values in the original object buffer.

Some ELF relocations require adding the a value to the original contents of the object buffer at the specified location.  In order to properly handle multiple applications of a relocation, the RuntimeDyld code should be grabbing the original value from the object buffer and writing a new value into the loaded section buffer.  This patch changes the parameters passed to resolveRelocations to accommodate this need.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167304 91177308-0d34-0410-b5e6-96231b3b80d8