Rewrite c_value_print_inner

Rewrite c_value_print_inner

This rewrites c_value_print_inner, copying in the body of
c_val_print_inner and adusting as needed.  This will form the base of
future changes to fully convert this to using the value-based API

gdb/ChangeLog
2020-03-13  Tom Tromey  <tom@tromey.com>

	* c-valprint.c (c_value_print_inner): Rewrite.