[1/17] make minimal_symbol::filename const

[Tom Tromey]

>>>>> "Tom" == Tom Tromey <tromey@redhat.com> writes:

Tom> A trivial one.  I will probably just put it in.

I am checking this in with this ChangeLog entry:

2011-12-21  Tom Tromey  <tromey@redhat.com>

	* symtab.h (struct minimal_symbol) <filename>: Now const.

Tom