Problem building GDB on Power64

[Paul Gilliam]

On a ppc64 system, GDB builds as a 32-bit application.  This is OK if the 
64-bit dev. env. is not available.  But if it is, this is wrong: GDB should 
build as a 64-bit application so that both 64 and 32 bit apps can be 
debugged.

If I understood the configure process, I would have tried submitting a patch.  
It should be easy: just include -m64 in the CFLAGS.  And make sure to link 
with the 64-bit libraries (which had better be there).

-=# Paul Gilliam #=-