Remove call to dwarf2_per_objfile::adjust from ranges readers

dwarf2_per_objfile::adjust applies gdbarch_adjust_dwarf2_addr to an
address, leaving the result unrelocated.  However, this adjustment is
only needed for text-section symbols -- it isn't needed for any sort
of address mapping.  Therefore, these calls can be removed from
read_addrmap_from_aranges and create_addrmap_from_gdb_index.

Approved-By: Andrew Burgess <aburgess@redhat.com>