elfcopy: include extension but replace . when converting from binary

[emaste]

Summary

The change in rS291958 was not consistent with GNU objcopy. The start/end/size symbols created for ELF objects converted from binary need to include the full filename including the extension, but with periods replaced with underscores.

[emaste]

readelf -s shows the following for a fuzz.txt file converted to ELF:

Symbol table '.symtab' contains 5 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND 
     1: 0000000000000000     0 SECTION LOCAL  DEFAULT    1 
     2: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT    1 _binary_fuzz_txt_start
     3: 00000000000011d0     0 NOTYPE  GLOBAL DEFAULT    1 _binary_fuzz_txt_end
     4: 00000000000011d0     0 NOTYPE  GLOBAL DEFAULT  ABS _binary_fuzz_txt_size

[emaste]

Check for failure from strdup

[emaste]

Committed upstream in r3270