to new file top.c. Make things extern instead of static and
similar rearrangements to deal with this.
* top.h: New file.
* utils.c: Move fputs_unfiltered to main.c. Remove
FPUTS_UNFILTERED_OVERRIDE ifndef.
* Makefile.in: Change so that gdb uses main.c, utils.c, and top.c,
and libgdb uses utils.c and top.c.