Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
The testcase was failing on various 64bit platforms, because the
debugging info said that the target type for a const type is a
4-byte reference. In the asm file, I used a .long directive, but
the size of .long is of course dependent on the platform. This
replaces this .long by a .4byte directive.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/dw2-const.S: Use .4byte to reference the target
type of our const type.
