i965: Delete brw_print_reg() function.

i965: Delete brw_print_reg() function.

This wasn't called from anywhere; presumably it was used to examine
brw_regs when debugging shader assembly.  However, it prints registers
in a different notation than brw_disasm.c which everyone is used
to...which means I doubt anyone will want to use it.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Chad Versace <chad.versace@linux.intel.com>