Resolve hard-coded libdynamorio name in memquery.

At least in Linux.

Currently, the library name is hard-coded as DYNAMORIO_LIBRARY_NAME and is used in compares in memquery. If the actual name diverts from this, the loader bails / takes the wrong path (i.e. falsely detecting app maps overlap).

Support drrun -use_dll ./randomname.so -- and drrun -use_dll ./libdynamorio.so -- w/ libdynamorio.so being symlink to randomname.so.