RFA: symfile.c: Fix for GDB crash when rereading symbols

[Michael Snyder]

Peter.Schauer wrote:
> 
> symfile.c:reread_symbols does not clear the new msymbol hash tables in the
> objfile, causing stale pointers and a GDB crash during the reread.exp
> test on Solaris.
> 
> Here is a fix:
> 
>         * symfile.c (reread_symbols):  Clear msymbol hash table.

I've checked it in.  Thanks again.

			Michael