Fixed an issue where we might not find global variables by name when we have

a debug map with DWARF in the .o files due to the attemted shortcut that was
being taken where the global variables were being searched for by looking in
the symbol table. The problem with the symbols in the symbol table is we don't
break apart the symbol names for symbols when they are mangled into basename
and the fully mangled name since this would take a lot of CPU time to chop up
the mangled names and try and find the basenames. The DWARF info typically has
this broken up for us where the basename of the variable is in a the DW_AT_name
attribute, and the mangled name is in the DW_AT_MIPS_linkage_name attribute.
Now we correctly find globals by searching all OSO's for the information so we
can take advantage of this split information. 

llvm-svn: 119012